Sole construction for footwear having metal components

ABSTRACT

A sole construction for supporting at least a portion of a human foot and for providing energy storage and return is provided. The sole construction includes a generally horizontal layer of stretchable material, at least one chamber positioned adjacent a first side of the layer, and at least one actuator positioned adjacent a second side of the layer vertically aligned with a corresponding chamber. Each actuator has a footprint size smaller than that of the corresponding chamber, and is sized and arranged to provide individual support to the bones of the human foot. The support structure when compressed causes the actuator to push against the layer and move the layer at least partially into the corresponding chamber. In one embodiment, a plurality of actuators are provided that are made of a metallic material such as magnesium, titanium, aluminum or steel.

CROSS-REFERENCE TO RELATED APPLICATION

[0001] This application claims the benefit of U.S. ProvisionalApplication No. 60/388679, filed Jun. 12, 2002, the entirety of which ishereby incorporated by reference.

BACKGROUND OF THE INVENTION

[0002] 1. Field of the Invention

[0003] The present invention generally relates to articles of footwear,and more particularly, to a sole construction that may be incorporatedinto athletic footwear or as an insert into existing footwear and thelike in order to store kinetic energy generated by a person. The soleconstruction has a combination of structural features enabling enhancedstorage, retrieval and guidance of wearer muscle energy that complementand augment performance of participants in recreational and sportsactivities.

[0004] 2. Description of the Related Art

[0005] From the earliest times when humans began wearing coverings ontheir feet, there has been an ever present desire to make such coveringsmore useful and more comfortable. Accordingly, a plethora of differenttypes of footwear has been developed in order to meet specialized needsof a particular activity in which the wearer intends to participate.Likewise, there have been many developments to enhance the comfort levelof both general and specialized footwear.

[0006] The human foot is unique in the animal kingdom. It possessesinherent qualities and abilities far beyond other animals. We can movebi-pedially across the roughest terrain. We can balance on one foot, wecan sense the smallest small grain of sand in our shoes. In fact, wehave more nerve endings in our feet than our hands.

[0007] We literally roll forward, rearward, laterally and mediallyacross the bony structures of the foot. The key word is “roll.” Themuscles of the foot and ankle system provide a controlled accelerationof forces laterally to medially and vise-versa across the bony structureof the foot. In bio-mechanical terms these motions are referred to aspronation and supination. The foot is almost never applied flat, inrelative position to the ground, yet shoe designers continue toanticipate this event.

[0008] The increasing popularity of athletic endeavors has beenaccompanied by an increasing number of shoe designs intended to meet theneeds of the participants in the various sports. The proliferation ofshoe designs has especially occurred for participants in athleticendeavors involving rigorous movements, such as walking, running,jumping and the like. In typical walking and running gaits, it is wellunderstood that one foot contacts the support surface (such as theground) in a “stance mode” while the other foot is moving through theair in a “swing mode.” Furthermore, in the stance mode, the respectivefoot “on the ground” travels through three successive basic phases: heelstrike, mid stance and toe off. At faster running paces, the heel strikephase is usually omitted since the person tends to elevate onto his/hertoes.

[0009] Typical shoe designs fail to adequately address the needs of theparticipant's foot and ankle system during each of these successivestages. Typical shoe designs cause the participant's foot and anklesystem to lose a significant proportion, by some estimates at leastthirty percent, of its functional abilities including its abilities toabsorb shock, load musculature and tendon systems, and to propel therunner's body forward.

[0010] This is because the soles of current walking and running shoedesigns fail to address individually the muscles and tendons of aparticipant's foot. The failure to individually address these footcomponents inhibits the flexibility of the foot and ankle system,interferes with the timing necessary to optimally load the foot andankle system, and interrupts the smooth and continuous transfer ofenergy from the heel to the toes of the foot during the three successivebasic phases of the “on the ground” foot travel.

[0011] Moreover, in vigorous athletic activities, the athlete generateskinetic energy from the motion of running, jumping, etc. Traditionalshoe designs have served merely to dampen the shock from theseactivities thereby dissipating that energy. Rather than losing thekinetic energy produced by the athlete, it is useful to store andretrieve that energy thereby enhancing athletic performance. Traditionalshoe construction, however, has failed to address this need.

[0012] Historically, manufacturers of modern running shoes added foam tocushion a wearer's foot. Then, gradually manufacturers developed otheralternatives to foam-based footwear for the reason that foam becomespermanently compressed with repeated use and thus ceases to perform thecushioning function. One of the largest running shoe manufacturers,Nike, Inc. of Beaverton, Oreg., has utilized bags of compressed gas asthe means to cushion the wearer's foot. A German manufacturer, Puma AG,has proposed a foamless shoe in which polyurethane elastomer is thecushioning material. Another running shoe manufacturer, ReebokInternational of Stoughton, Mass., recently introduced a running shoewhich has two layers of air cushioning. Running shoe designersheretofore have sought to strike a compromise between providing enoughcushioning to protect the wearer's heel but not so much that thewearer's foot will wobble and get out of sync with the working of theknee. The Reebok shoe uses air that moves to various parts of the soleat specific times. For example, when the outside of the runner's heeltouches ground, it lands on a cushion of air. As the runner's weightbears down, that air is pushed to the inside of the heel, which keepsthe foot from rolling inward too much while another air-filled layer isforcing air toward the forefoot. When the runner's weight is on theforefoot, the air travels back to the heel.

[0013] In the last several years, there have been some attempts toconstruct athletic shoes that provide some rebound thereby returningenergy to the athlete. Various air bladder systems have been employed toprovide a “bounce” during use. In addition, there have been numerousadvancements and materials used to construct the sole and the shoe in aneffort to make them more “springy.”

[0014] Furthermore, midsole and sole compression, historically speaking,can be very destabilizing. This is because pitching, tipping and lateralshear of the sole and midsole naturally rebound energies in the oppositedirection required for control and energy transfers. Another perplexingproblem for shoe engineers has been how to store energy as the foot andankle system rolls laterally to medially. These rotational forces havebeen very difficult to absorb and control.

[0015] No past shoe designs, including the specific ones cited above,are believed to adequately address the aforementioned needs of theparticipant's foot and ankle system during walking and runningactivities in a manner that augments performance. The past approaches,being primarily concerned with cushioning the impact of the wearer'sfoot with the ground surface, fail to even recognize, let alone begin toaddress, the need to provide features in the shoe sole that will enhancethe storage, retrieval and guidance of a wearer's muscle energy in a waythat will complement and augment the wearer's performance duringwalking, running and jumping activities.

[0016] U.S. Pat. No. 5,595,003 to Snow discloses an athletic shoe with aforce responsive sole. However, among the problems with the Snowembodiments is that they teach very thick soles comprised of tallcleats, a resilient membrane, deep apertures, and “guide plates.” Thecombination of these components is undesirable because they make up avery heavy shoe. Furthermore, Snow shows numerous small parts that wouldbe cost prohibitive to manufacture. These numerous small cleats cannotaffect enough rubber molecules through the resilient membrane to providea competitive efficiency gain without increasing the thickness of themembrane to the point of impracticability. The heavier and tallermidsole and sole of Snow also position the foot further from the ground,providing less stability as well as less neuro-muscular input. Moreover,it takes a longer period of time for Snow's cleats to “cycle,” i.e.,penetrate and rebound. This produces a limiting effect for performanceand efficiency gain potential.

[0017] Snow's cleats also require vertical guidance, i.e., anti-tipping,such as by Snow's required guide plate. Snow also fails to provideappropriate points of leverage for specific bone structures of the foot,control over the intrinsic rotational involvement of the foot and anklesystem, bio-mechanical guidance, and the ability to produce tunablevertical vectors and transfer energy forward and rearward from heel,midfoot, forefoot and toes and vice-versa.

[0018] In my earlier invention disclosed in U.S. Pat. No. 5,647,145issued Jul. 15, 1997, I teach an athletic footwear sole constructionthat enhances the performance of the shoe in several ways. First, theconstruction described in the '145 patent individually addresses theheel, toe, tarsal and metatarsal regions of the foot to allow moreflexibility so that the various portions of the sole cooperate withrespective portions of the foot. In addition, a resilient layer isprovided in the sole which cooperates with cavities formed at variouslocations to help store energy.

[0019] While the advancements in shoe construction described above,including the '145 patent, have provided a great benefit to the athlete,there remains a continued need for increased performance of athleticfootwear. There remains a need for an athletic footwear soleconstruction that can store an increased amount of kinetic energy andreturn that energy to the athlete to improve athlete performance.

SUMMARY OF THE INVENTION

[0020] It is an object of the present invention to provide a new anduseful sole construction that may be incorporated into footwear or usedas an insert into existing footwear.

[0021] It is another object of the present invention to provide astructure for use with footwear that stores kinetic energy when acompressive weight is placed thereon and which releases that energy whenthe weight is taken off.

[0022] It is a further object of the present invention to providefootwear and, specifically, a sole construction therefor, that enhancesthe performance of a person wearing the footwear.

[0023] The present invention provides an athletic footwear soleconstruction designed to satisfy the aforementioned needs. In one aspectof the present invention, the athletic footwear sole provides acombination of structural features under the heel, midfoot and forefootregions of the wearer's foot that enable enhanced storage, retrieval andguidance of muscle energy in a manner that complements and augmentswearer performance in sports and recreational activities. The soleconstruction of the present invention enables athletic footwear forwalking, running and jumping to improve and enhance performance bycomplementing, augmenting and guiding the natural flexing actions of themuscles of the foot. The combination of structural features incorporatedin the sole construction of the present invention provides uniquecontrol over and guidance of the energy of the wearer's foot as ittravels through the three successive basic phases of heel strike, midstance and toe off.

[0024] Accordingly, one aspect of the present invention is directed toan athletic footwear having an upper and sole with the sole having heel,midfoot, metatarsal, and toe regions wherein the sole comprises afoundation layer of stiff material attached to the upper and defining aplurality of stretch chambers, a stretch layer attached to thefoundation layer and having portions of elastic stretchable materialunderlying the stretch chambers of the foundation layer, and a thrustorlayer attached to the stretch layer and having portions of stiffmaterial underlying and aligned with the stretch chambers of thefoundation layer and with the portions of the stretch layer disposedbetween the thrustor layer and foundation layer. Given the above-definedarrangement, interactions occur between the foundation layer, stretchlayer and thrustor layer in response to compressive forces appliedthereto upon contact of the heel and midfoot regions and metatarsal andtoe regions of the sole with a support surface so as to convert andtemporarily store energy applied to heel and midfoot regions andmetatarsal and toe regions of the sole by a wearer's foot intomechanical stretching of the portions of the stretch layer into thestretch chambers of the foundation layer. The stored energy isthereafter retrieved in the form of rebound of the stretched portions ofthe stretch layer and portions of the thrustor layer. Whereas componentsof the heel and midfoot regions of the sole provide temporary storageand retrieval of energy at central and peripheral sites underlying theheel and midfoot of the wearer's foot, components of the metatarsal andtoe regions of the sole provide the temporary storage and retrieval ofenergy at independent sites underlying the individual metatarsals andtoes of the wearer's foot.

[0025] In another aspect of the present invention, a sole is adapted foruse with an article of footwear to be worn on the foot of a person whilethe person traverses along a support surface. This sole is operative tostore and release energy resulting from compressive forces generated bythe person's weight on the support surface. This sole is thus animprovement which can be incorporated with standard footwear uppers.Alternatively, the invention can be configured as an insert sole whichcan be inserted into an existing shoe or other article of footwear.

[0026] In one embodiment, the sole has a first layer of stretchableresilient material that has opposite first and second surfaces. A firstprofile is formed of a stiff material and is positioned on the firstside of the resilient layer. The first profile includes a first profilechamber formed therein. This first profile chamber has an interiorregion opening toward the first surface of the resilient layer. Thefirst profile and the resilient layer are positioned relative to oneanother so that the resilient layer spans across the first interiorregion. A second profile is also formed of a stiff material and ispositioned on the second side of the resilient layer opposite the firstprofile. This second profile includes a primary actuator element thatfaces the second surface of the resilient layer to define a staticstate. The first and second profiles are positioned relative to oneanother with the primary actuator element being oriented relative to thefirst profile chamber such that the compressive force between the footand the support surface will move the first and second profiles towardone another. When this occurs, the primary actuator element advancesinto the first profile chamber thereby stretching the resilient layerinto the interior region defining an active state. In the active state,energy is stored by the resilient layer, and the resilient layerreleases this energy to move the first and second profiles apart uponremoval of the compressive force.

[0027] Preferably, the second profile has a second profile chamberformed therein. This second profile chamber has a second interior regionopening toward the second surface of the resilient layer so that theresilient layer also spans across this second region. A plunger elementis then provided and is disposed in the first interior region. Thisplunger element moves into and out of the second interior region whenthe first and second profiles move between the static and active states.Here, also, a plurality of plunger elements may be disposed in the firstinterior region with these plunger elements operative to move into andout of the second interior region when the first and second profilesmove between the static and active states. The plunger element may beformed integrally with the first layer of resilient material.

[0028] A third profile may also be provided, with this third profilehaving a third profile chamber formed therein. This third profilechamber has a third interior region. Here, a second layer of stretchableresilient material spans across the third region. The first profile thenincludes a secondary actuator element positioned to move into the thirdinterior region and to stretch the second layer of resilient materialinto the third profile chamber in response to the compressive force. Thefirst profile may also include a plurality of second actuators, andthese actuators may extend around a perimeter thereof to define thefirst profile chamber. The third profile then has a plurality of thirdchambers each including a second layer of resilient material that spansthereacross. These third profile chambers are each positioned to receivea respective one of the secondary actuators. The first profile in thesecond actuator may also be formed as an integral, one-piececonstruction. The third profile and the plunger element may also beformed as an integral, one-piece construction.

[0029] The sole according to the present invention can be a sectionselected from the group consisting of heel sections, metatarsal sectionsand toe sections. Preferably, the sole includes one of each of thesesections so as to underlie the entire foot but to provide independentenergy storing support for each of the three major sections of the foot.Alternatively, the present invention may be used in connection with onlyone or two sections of the foot. In any event, the invention allowseither of the first or second profiles to operate in contact with thesupport surface.

[0030] The present invention also contemplates an article of footwearincorporating the sole, as described above, in combination with afootwear upper. In addition, the present invention contemplates aninsert sole adapted for insertion into an article of footwear.

[0031] In another aspect of the present invention, a support structureprovides energy storage and return to at least a portion of a humanfoot. This support structure comprises a generally horizontal layer ofstretchable material, at least one chamber positioned adjacent a firstside of the layer, and at least one actuator positioned adjacent asecond side of the layer vertically aligned with a correspondingchamber. Each actuator has a footprint size smaller than that of thecorresponding chamber. The support structure when compressed causes theactuator to push against the layer and move the layer at least partiallyinto the corresponding chamber. Each actuator is selectively positionedto provide individual support to a portion of the human foot selectedfrom the group consisting of a toe, a metatarsal bone, a midfoot portionand a heel portion.

[0032] In another embodiment, an energy storage and return system forfootwear and the like is provided. The system comprises at least twostretchable layer portions, each of the portions having an upper sideand a lower side. A plurality of actuator elements is provided, whereinat least one of the actuator elements is positioned above a stretchablelayer portion and at least one of the actuator elements is positionedbelow a stretchable layer portion. A plurality of receiving chambers isalso provided, wherein each receiving chamber corresponds to one of theactuator elements and is sized and positioned to receive at leastpartially the corresponding actuator element therein when the actuatorelements are compressed toward the receiving chambers. Each of thereceiving chambers is preferably located opposite a correspondingactuator element across a stretchable layer portion.

[0033] In another aspect of the present invention, an energy returnsystem for footwear and the like is provided. This system comprises atleast one layer of stretchable material having a first side and a secondside. A plurality of chambers is positioned on either the first side orthe second side of the layer. A plurality of actuators each verticallyaligned with a corresponding chamber is positioned opposite the chambersacross at least one layer of stretchable material, each actuator havinga footprint size smaller than that of the chamber. When the footwearreceives a generally vertical compressive force, the actuator pushesagainst the layer and moves at least partially into a chamber. Theactuators are patterned according to the structure of the human foot.

[0034] In another aspect of the present invention, a sole constructionfor underlying at least a portion of a human foot is provided. This soleconstruction comprises a generally horizontal layer of stretchablematerial having a first side and a second side. A chamber layer having achamber therein is positioned on the first side of the layer ofstretchable material, the chamber having at least one opening facing thefirst side of the layer of stretchable material. An actuator ispositioned on the second side of the layer of stretchable material, theactuator having a footprint size that is smaller than that of theopening of the chamber such that when the sole construction iscompressed, the actuator presses against the second side of the layer ofstretchable material and at least partially into the chamber of thechamber layer. The actuator is at least partially tapered, which, asused herein, refers to a dimensional reduction in the size of theactuator, either in a vertical or a horizontal direction. For instance,the tapering of the actuator can refer to a vertical decrease inthickness of the actuator, such as by giving the actuator a dome-likeshape or sloping surfaces, or by reducing the height or other dimensionof the actuator horizontally, such as by tapering or sloping the upperor lower surface of the actuator towards the front of the foot.

[0035] In another aspect of the present invention, a sole constructionfor supporting at least a portion of a human foot is provided. This soleconstruction comprises a generally horizontal layer of stretchablematerial having a first side and a second side. A profile piece having aprimary chamber therein is positioned on the first side of the layer ofstretchable material, the primary chamber having at least one openingfacing the first side of the layer of stretchable material. A primaryactuator is positioned on the second side of the layer of stretchablematerial, the primary actuator having a footprint size that is smallerthan that of the opening of the primary chamber such that when the soleconstruction is compressed, the primary actuator presses against thesecond side of the layer of stretchable material and at least partiallyinto the primary chamber of the first layer. A secondary chamber ispositioned within the primary actuator, the secondary chamber having atleast one opening facing the second side of the layer of stretchablematerial. A secondary actuator is positioned on the first side of thelayer of stretchable material, the secondary actuator having a footprintsize that is smaller than that of the opening of the secondary chambersuch that when the sole construction is compressed, the secondaryactuator presses against the first side of the layer of stretchablematerial and at least partially into the secondary chamber.

[0036] In another aspect of the present invention, a heel portion for asole construction is provided. The heel portion comprises a mainthrustor, a first layer of stretchable material positioned above themain thrustor, and a satellite thrustor layer positioned above the firstlayer of stretchable material. The satellite thrustor has an uppersurface and a lower surface, the upper surface of the satellite thrustorlayer preferably having a plurality of satellite thrustors extendingupwardly therefrom. The satellite thrustor layer also has a centralopening therein. The heel portion further comprises a second layer ofstretchable material positioned above the satellite thrustor layer and afoundation layer positioned above the second layer of stretchablematerial. The foundation layer preferably has an upper surface and alower surface and a plurality of satellite openings positioned toreceive the satellite thrustors. The heel portion when compressed causesthe main thrustor to stretch through the first layer of stretchablematerial at least partially into the central opening of the satellitethrustor layer and the satellite thrusters to stretch through the secondlayer of stretchable material at least partially into the satelliteopenings.

[0037] In another aspect of the present invention, a sole constructionis provided comprising a generally horizontal layer of stretchablematerial, a plurality of chambers positioned adjacent a first side ofthe layer, and a plurality of interconnected actuator elementspositioned adjacent a second side of the layer. Each actuator element isvertically aligned with a corresponding chamber and has a footprint sizesmaller than that of the corresponding chamber. The support structurewhen compressed causes the actuator element to push against the layerand move the layer at least partially into the corresponding chamber.

[0038] These and other features and advantages of the present inventionwill become apparent to those skilled in the art upon a reading of thefollowing detailed description when considered in connection with thedrawings which show and describe exemplary embodiments of the invention.

BRIEF DESCRIPTION OF THE DRAWINGS

[0039]FIG. 1 is a side elevational view of an athletic footwear soleconstruction in a first exemplary embodiment of the present invention.

[0040]FIG. 2 is a front elevational view of the sole construction ofFIG. 1.

[0041]FIG. 3 is an exploded top perspective view of heel and midfootregions of the sole construction.

[0042]FIG. 4 is an exploded bottom perspective view of heel and midfootregions of the sole construction.

[0043]FIG. 5 is a rear end view of the heel region of the soleconstruction shown in a relaxed condition.

[0044]FIG. 6 is a vertical transverse sectional view of the soleconstruction of FIG. 5.

[0045]FIG. 7 is a rear end view of the heel region of the soleconstruction shown in a loaded condition.

[0046]FIG. 8 is a vertical transverse sectional view of the soleconstruction of FIG. 7.

[0047]FIG. 9 is an exploded top perspective view of the metatarsal andtoe regions of the sole construction of the present invention.

[0048]FIG. 10 is a vertical transverse sectional view of the metatarsalregion of the sole construction shown in a relaxed condition.

[0049]FIG. 11 is a vertical transverse sectional view of the metatarsalregion of the sole construction shown in a loaded condition.

[0050]FIG. 12 is a side view in elevation of a second exemplaryembodiment of an article of footwear incorporating the heel portion ofthe sole according to the second exemplary embodiment of the presentinvention.

[0051]FIG. 13 is an exploded perspective view of the heel portion of thearticle of footwear shown in FIG. 12.

[0052]FIG. 14A is a side view in cross-section showing the heel portionof FIGS. 12 and 13 in a static state.

[0053]FIG. 14B is a side view in cross-section, similar to FIG. 14Aexcept showing the heel portion in an active state.

[0054]FIG. 15 is a side view in elevation of an article of footwearhaving a sole constructed according to a third exemplary embodiment ofthe present invention.

[0055]FIG. 16 is an end view in elevation of the article of footwearshown in FIG. 15.

[0056]FIG. 17 is an exploded perspective view of the heel portion of thearticle of footwear shown in FIG. 15.

[0057]FIG. 18 is a side view in a partial cross-sectional and explodedview to show the construction of the heel portion of FIG. 17.

[0058]FIG. 19A is a rear end view in cross-section showing the heelportion of the sole of the article of footwear of FIG. 15 in a staticstate.

[0059]FIG. 19B is a cross-sectional view, similar to FIG. 19A butshowing the heel portion in an active state.

[0060]FIG. 20A is a top plan view of the first profile used for the toeportion of the sole of FIG. 15.

[0061]FIG. 20B is a top plan view of the resilient layer used to formthe toe portion of the sole of FIG. 15.

[0062]FIG. 20C is a top plan view of the second profile used to form thetoe portion of the sole of FIG. 15.

[0063]FIG. 20D is a perspective view of an alternative construction ofthe resilient layer for the toe portion of the sole of FIG. 15.

[0064]FIG. 21A is a cross-sectional view of the toe portion of the soleof FIG. 20 shown in a static state.

[0065]FIG. 21B is a cross-sectional view similar to FIG. 21A but showingthe toe portion in an active state.

[0066]FIG. 22A is a top plan view of the first profile used to form themetatarsal portion of the sole of FIG. 15.

[0067]FIG. 22B is a top plan view of the resilient layer used to formthe metatarsal portion of the sole of FIG. 15.

[0068]FIG. 22C is a top plan view of the second profile used to form themetatarsal portion of the sole of FIG. 15.

[0069]FIG. 23 is a side view in elevation showing a sole insertaccording to a fourth exemplary embodiment of the present invention.

[0070]FIG. 24 is a cross-sectional view taken about lines 24-24 of FIG.23.

[0071]FIG. 25A is a perspective view of the first profile used to formthe toe portion of the sole insert of FIG. 23.

[0072]FIG. 25B is a perspective view of the second profile used to formthe toe portion of the sole insert of FIG. 23.

[0073]FIG. 26A is a perspective view of the first profile used to formthe metatarsal portion of the sole insert of FIG. 23.

[0074]FIG. 26B is a perspective view of the second profile used to formthe metatarsal portion of the sole insert of FIG. 23.

[0075]FIG. 27A is a perspective view of the first profile used to formthe heel portion of the sole insert of FIG. 23.

[0076]FIG. 27B is a perspective view of the second profile used to formthe heel portion of the sole insert of FIG. 23.

[0077]FIG. 28 is an exploded perspective view of the heel portion of anarticle of footwear according to a fifth exemplary embodiment.

[0078]FIG. 29 is a side view in a partial cross-sectional and explodedview to show the construction of the heel portion of FIG. 28.

[0079]FIG. 30 is a bottom elevational view of the sole of FIG. 28.

[0080]FIG. 31A is a top plan view of the first profile used for theadditional metatarsal support portion of the sole of FIG. 30.

[0081]FIG. 31B is a top plan view of the resilient layer used to formthe additional metatarsal support portion of the sole of FIG. 30.

[0082]FIG. 31C is a top plan view of the second profile used to form theadditional metatarsal portion of the sole of FIG. 30.

[0083]FIG. 32 is an exploded perspective view of the heel portion of anarticle of footwear according to a sixth exemplary embodiment.

[0084]FIG. 33 is a side view in a partial cross-sectional and explodedview to show the construction of the heel portion of FIG. 32.

[0085]FIG. 34 is an exploded perspective view of a seventh exemplaryembodiment of the sole construction of the present invention.

[0086]FIG. 35 is a perspective view of the main thrustor of the soleconstruction of FIG. 34.

[0087]FIG. 36 is a bottom plan view of the main thrustor of the soleconstruction of FIG. 34.

[0088]FIG. 37 is cross-sectional view of the main thrustor of FIG. 36,taken along line 37-37.

[0089]FIG. 38 is a cross-sectional view of the main thrustor of FIG. 36,taken along line 38-38.

[0090]FIG. 39 is a perspective view of the first resilient layer of FIG.34.

[0091]FIG. 40 is a bottom plan view of the first resilient layer of FIG.34.

[0092]FIG. 41 is a cross-sectional view of the first resilient layer ofFIG. 40, taken along line 41-41.

[0093]FIG. 42 is a perspective view of the satellite thrustor layer ofFIG. 34.

[0094]FIG. 43 is a bottom plan view of the satellite thrustor layer ofFIG. 34.

[0095]FIG. 44 is a cross-sectional view of the satellite thrustor layerof FIG. 43, taken along line 44-44.

[0096]FIG. 45 is a perspective view of the second resilient layer ofFIG. 34.

[0097]FIG. 46 is a bottom plan view of the second resilient layer ofFIG. 34.

[0098]FIG. 47 is a cross-sectional view of the second resilient layer ofFIG. 46, taken along line 47-47.

[0099]FIG. 48 is a perspective view of the secondary thrustor layer ofFIG. 34.

[0100]FIG. 49 is a bottom plan view of the secondary thrustor layer ofFIG. 34.

[0101]FIG. 50 is a cross-sectional view of the secondary thrustor layerof FIG. 49, taken along line 50-50.

[0102]FIG. 51 is a cross-sectional view of the secondary thrustor layerof FIG. 49, taken along line 51-51.

[0103]FIG. 52 is a perspective view of the toe actuator layer of FIG.34.

[0104]FIG. 53 is a bottom plan view of the toe actuator layer of FIG.34.

[0105]FIG. 54 is a cross-sectional view of the toe actuator layer ofFIG. 53, taken along line 54-54.

[0106]FIG. 55 is a cross-sectional view of the toe actuator layer ofFIG. 53, taken along line 55-55.

[0107]FIG. 56 is a perspective view of the toe chamber layer of FIG. 34.

[0108]FIG. 57 is a bottom plan view of the toe chamber layer of FIG. 34.

[0109]FIG. 58 is a cross-sectional view of the toe chamber layer of FIG.57, taken along line 58-58.

[0110]FIG. 59 is a cross-sectional view of the toe chamber layer of FIG.57, taken along line 59-59.

[0111]FIG. 60 is a perspective view of the forefoot actuator layer ofFIG. 34.

[0112]FIG. 61 is a bottom plan view of the forefoot actuator layer ofFIG. 34.

[0113]FIG. 62 is a cross-sectional view of the forefoot actuator layerof FIG. 61, taken along line 62-62.

[0114]FIG. 63 is a cross-sectional view of the forefoot actuator layerof FIG. 61, taken along line 63-63.

[0115]FIG. 64 is a cross-sectional view of the forefoot actuator layerof FIG. 61, taken along line 64-64.

[0116]FIG. 65 is a perspective view of the forefoot chamber layer ofFIG. 34.

[0117]FIG. 66 is a bottom plan view of the forefoot chamber layer ofFIG. 34.

[0118]FIG. 67 is a cross-sectional view of the forefoot chamber layer ofFIG. 65, taken along line 67-67.

[0119]FIG. 68 is a cross-sectional view of the forefoot chamber layer ofFIG. 65, taken along line 68-68.

[0120]FIG. 69 is a perspective view of a toe traction layer.

[0121]FIG. 70 is a bottom plan view of the toe traction layer of FIG.69.

[0122]FIGS. 71 and 72 are side views of the toe traction layer of FIG.69.

[0123]FIG. 73 is a perspective view of a forefoot traction layer.

[0124]FIG. 74 is a bottom plan view of the forefoot traction layer ofFIG. 73.

[0125]FIGS. 75 and 76 are side views of the forefoot traction layer ofFIG. 73.

[0126]FIG. 77 is a perspective view of an eighth exemplary embodiment ofthe sole construction of the present invention.

[0127] FIGS. 78-82 illustrate the main thrustor of the sole constructionof FIG. 77.

[0128] FIGS. 83-86 illustrate the first resilient layer in the heelportion of the sole construction of FIG. 77.

[0129] FIGS. 87-90 illustrate the satellite thrustor layer of the soleconstruction of FIG. 77.

[0130] FIGS. 91-95 illustrate the second resilient layer in the heelportion of the sole construction of FIG. 77.

[0131] FIGS. 96-100 illustrate the secondary thrustor layer of the soleconstruction of FIG. 77.

[0132] FIGS. 101-105 illustrate the heel traction layer of the soleconstruction of FIG. 77.

[0133] FIGS. 106-109 illustrate the toe actuator layer of the soleconstruction of FIG. 77.

[0134] FIGS. 110-114 illustrate the resilient layer in the toe portionof the sole construction of FIG. 77.

[0135] FIGS. 115-117 illustrate the toe chamber layer of the soleconstruction of FIG. 77.

[0136] FIGS. 118-121 illustrate the toe traction layer of the soleconstruction of FIG. 77.

[0137] FIGS. 122-125 illustrate the metatarsal actuator layer of thesole construction of FIG. 77.

[0138] FIGS. 126-130 illustrate the resilient layer in the metatarsalportion of the sole construction of FIG. 77.

[0139] FIGS. 131-133 illustrate the metatarsal chamber layer of the soleconstruction of FIG. 77.

[0140] FIGS. 134-137 illustrate the metatarsal traction layer of thesole construction of FIG. 77.

[0141] FIGS. 138-141 illustrate the mid sole of the sole construction ofFIG. 77.

[0142] FIGS. 142-144 illustrate the mid sole traction layer of the soleconstruction of FIG. 77.

[0143] FIGS. 145-147 are perspective views of a shoe incorporating thesole construction of FIG. 77.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0144] The description provided hereinbelow illustrates eight exemplaryembodiments of a sole construction according to the present invention.It should be appreciated that each of these embodiments is merelyexemplary. Therefore, features from one or more of the embodiments maybe added or removed from other embodiments without departing from thescope of the invention. Furthermore, the energy storage and reboundcharacteristics as described in one embodiment may also be applicable tothe other embodiments when similar mechanisms are involved. Moreover, asused herein, the terms “thrustor,” “plunger,” “lug” and “actuator” aresubstantially interchangeable and generally refer to actuators used forthe storage and rebound of energy.

[0145] In general, the embodiments described below provide chamberedactuators patterned according to the structure of the foot. In theseembodiments, patterned rigidity ensures a smooth transfer of energies(the energy “wave”) across the foot. The chambers provide holes for theenergy to flow into. Energy always follows the path of least resistance.The staggering of active support actuators and energy exchange chambersbalances and supports the intrinsic rolling action of metatarsal bones,toes and heel.

[0146] The controlled storing and rebound of energy as described hereindo not force the foot into undesired movement; rather it suppliessuperior position, force and speed information to allow supination andpronation controlling musculature to store and release energy from theenergy “wave” process. This produces an efficiency gain, a “tighteningup” of the foot's rotational passes through the neutral plane. Theresulting sequential stability manages complex energy transfers andstoring demands across the foot, enabling the predictable specificvertical vector rebound or thrust of energy required for measurableefficiency gains.

[0147] Multiple intrinsic rate limiting factors together control thespeed at which the human neuro-muscular system acts and reacts withinits natural environment. Rate limiting factors include the contractileproteins actin and myosin, the speed of neuro-muscular input andfeedback systems, the natural dash pot effect of involved musculature,the genetic makeup, i.e., ratio of fast to slow twitch muscle fibers,the individual training environment, etc.

[0148] With this in mind, there is an optimum speed at which muscleswill receive the most energy as well as force, position, perceivedresistance and speed information from the environment. Chamberedactuators provide a tunable environment for energy and environmentalinformation to be provided to the neuro-muscular skeletal system.Tighter tolerances and shorter drops produce sprint speed efficiencygains, while looser tolerances and increased drops produce slowerrunning speed efficiency gains.

[0149] Chambered actuators also resist tipping through the controlledstretching of the membrane externally and more importantly internally,balancing the stretch producing a lateral-to-medial cradling effect. Asdescribed below, chambered actuators can utilize either a rigid orrubber internal pattern lug offering optional compression of a rubberlug or the superior vertical guidance of a rigid, e.g., plastic,internal pattern lug.

[0150] Raised nesting patterns on the elastic layers provide additionalspecifically placed thickness while limiting additional weight.Chambered actuators produce a very small footprint in relationship tothe amount of surface area, “stretch zone,” activated by impact orweight bearing. This generates more power, less weight, less requiredactuator penetration and faster cycle time.

[0151] With these general concepts in mind, the embodiments of thepresent invention are described below.

First Exemplary Embodiment

[0152] Referring to the drawings and particularly to FIGS. 1 and 2,there is illustrated a first exemplary embodiment of an article ofathletic footwear for walking, running and/or jumping, being generallydesignated 10. The footwear 10 includes an upper 12 and a sole 14 havingheel and midfoot regions 14A, 14B and metatarsal and toe regions 14C,14D wherein are provided the structural features of the sole 14constituting the present invention. The sole 14 incorporating theconstruction of the present invention improves the walking, running andjumping performance of a wearer of the footwear 10 by providing acombination of structural features which complements and augments,rather than resists, the natural flexing actions of the muscles of thefoot to more efficiently utilize the muscular energy of the wearer.

[0153] Referring to FIGS. 1 and 3 to 8, the heel and midfoot regions14A, 14B of the sole 14 basically includes the stacked combination of afootbed layer 16, an upper stretch layer 18, an upper thrustor layer 20,a lower stretch layer 22, and a lower thrustor layer 24. The footbedlayer 16 of the sole 14 serves as a foundation for the rest of thestacked components of the heel and midfoot regions 14A, 14B. The footbedlayer 16 includes a substantially flat foundation plate 26 of semi-rigidsemi-flexible thin stiff material, such as fiberglass, whose thicknessis chosen to predetermine the degree of flexion (or bending) it canundergo in response to the load that will be applied thereto.

[0154] The foundation plate 26 has a heel portion 26A and a midfootportion 26B. The foundation plate 26 has a continuous interior lip 26Cencompassing a central opening 28 formed in the foundation plate 26which provides its heel portion 26A with a generally annular shape. Theflat foundation plate 26 also has a plurality of continuous interioredges 26D encompassing a corresponding plurality of elongated slots 30formed in the foundation plate 26 arranged in spaced apart end-to-endfashion so as to provide a U-shaped pattern of the slots 30 startingfrom adjacent to a forward end 26E of the foundation plate 26 andextending rearwardly therefrom and around the central opening 28. Theslots 30 are preferably slightly curved in shape and run along aperiphery 26F of the foundation plate 26 but are spaced inwardly fromthe periphery 26F thereof and outwardly from the central opening 28thereof so as to leave solid narrow borders respectively adjacent to theperiphery 26F and the central opening 28 of the foundation plate 26. Theslots 30 alone or in conjunction with recesses 32 of corresponding shapeand position in the bottom of the shoe upper 12 define a correspondingplurality of peripheral stretch chambers 34 in the foundation plate 26.

[0155] The upper stretch layer 18 is made of a suitable elasticmaterial, such as rubber, and includes a flexible substantially flatstretchable body 36 and a plurality of compressible lugs 38 formed onand projecting downwardly from the bottom surface 36A of the flatstretchable body 36 at the periphery 36B thereof. The peripheral profileof the flat stretchable body 36 of the upper stretch layer 18 generallymatches that of the flat foundation plate 26 of the footbed layer 16. Inthe exemplary embodiment shown in FIGS. 1, 3 and 5 to 8, thecompressible lugs 38 are arranged in a plurality of pairs thereof, suchas six in number, spaced apart along opposite lateral sides of the flatstretchable body 36. Other arrangements of the compressible lugs 38 arepossible so long as it adds stability to the sole 14. For ease ofmanufacture, the compressible lugs 38 are preferably integrally attachedto the flat stretchable body 36.

[0156] The upper thrustor layer 20 disposed below and aligned with theupper stretch layer 18 includes a substantially flat support plate 40preferably made of a relatively incompressible, semi-rigid semi-flexiblethin stiff material, such as fiberglass, having a construction similarto that of the flat foundation plate 26 of the footbed layer 16. Theflat support plate 40 may have a heel portion 40A and a midfoot portion40B. The support plate 40 also has a continuous interior rim 40Csurrounding a central hole 42 formed through the support plate 40 whichprovides its heel portion 40A with a generally annular shape. Thecentral hole 42 provides an entrance to a space formed between the flatstretchable body 36 of the upper stretch layer 18 and the flat supportplate 40 spaced therebelow which space constitutes a main centralstretch chamber 44 of said sole 14. The peripheral profile of the upperthrustor layer 20 generally matches the peripheral profiles of thefootbed layer 16 and upper stretch layer 18 so as to provide the sole 14with a common profile when these components are in an operative stackedrelationship with one on top of the other.

[0157] The upper thrustor layer 20 also includes a plurality ofstretch-generating thrustor lugs 46 made of a relatively incompressibleflexible material, such as plastics, and being mounted on the topsurface 40D of the flat support plate 40 and projecting upwardlytherefrom so as to space the flat support plate 40 below the flatstretchable body 36 of the upper stretch layer 18. The thrustor lugs 46are arranged in a spaced apart end-to-end fashion which corresponds tothat of the slots 30 in the foundation plate 26 so as to provide aU-shaped pattern of the thrustor lugs 46 starting from adjacent to aforward end 40E of the flat support plate 40 and extending rearwardtherefrom and around the central opening 42. The thrustor lugs 46 runalong a periphery 40F of the support plate 40 but are spaced inwardlytherefrom and outwardly from the central opening 42 of the support plate40 so as to leave solid narrow borders respectively adjacent to theperiphery 40F and the central opening 42 of the support plate 40.

[0158] The peripherally-located thrustor lugs 46 thus correspond inshape and position to the peripherally-located slots 30 in the flatfoundation plate 26 of the footbed layer 16 defining theperipherally-located stretch chambers 34. For ease of manufacture thethrustor lugs 46 are attached to a common thin sheet which, in turn, isadhered to the top surface 40D of the flat support plate 40.

[0159] The flat support plate 40 of the upper thrustor layer 20 supportsthe thrustor lugs 46 in alignment with the slots 30 and thus with theperipheral stretch chambers 34 of the foundation plate 26 and upper 12of the shoe 10. However, the flat stretchable body 36 of upper stretchlayer 18 is disposed between the stretch generating thrustor lugs 46 andflat foundation plate 26. Thus, with the footbed layer 16, upper stretchlayer 18 and upper thrustor layer 20 disposed in the operative stackedrelationship with one on top of the other in the heel and midfootregions 14A, 14B of the sole 14, spaced portions 36C of the flatstretchable body 36 of the upper stretch layer 18 overlie top ends 46Aof the stretch-generating thrustor lugs 46 and underlie the peripheralstretch chambers 34. Upon compression of the footbed layer 16 and upperthrustor layer 20 toward one another from a relaxed condition shown inFIGS. 5 and 6 toward a loaded condition shown in FIGS. 7 and 8, asoccurs upon impact of the heel and midfoot regions 14A, 14B of the sole14 of the shoe 10 with a support surface, the spaced portions 36A of theflat stretchable body 36 are forcibly stretched by the upwardly movementof the top ends 46A of the thrustor lugs 46 upwardly past the interioredges 26D of the foundation plate 26 surrounding the slots 30 and intothe stretch chambers 34. This can occur due to the fact that thethrustor lugs 46 are enough smaller in their footprint size than that ofthe slots 30 so as to enable their top ends 46A together with theportions 36A of the flat stretchable body 36 stretched over the top ends46A of the thrustor lugs 46 to move and penetrate upwardly through theslots 30 and into the peripheral stretch chambers 34, as shown in FIGS.7 and 8.

[0160] The compressible lugs 38 of the upper stretch layer 18 arelocated in alignment with the solid border extending along the periphery26F of the foundation plate 26 outside of the thrustor lugs 46. Thecompressible lugs 38 project downwardly toward the support base 40. Thecompressive force applied to the foundation plate 26 of the footbedlayer 16 and to the support plate 42 of the upper thrustor layer 20,which occurs during normal use of the footwear 10, causes compression ofthe compressible lugs 38 from their normal tapered shape assumed in therelaxed condition of the sole 14 shown in FIGS. 5 and 6, into the bulgedshape taken on in the loaded condition of the sole 14 shown in FIGS. 7and 8. In addition to adding stability, the function of the compressiblelugs 38 is to provide storage of the energy that was required tocompress the lugs 38 and thereby to quicken and balance the resistanceand rebound qualities of the sole 14

[0161] As can best be seen in FIGS. 1 and 3, the stretch-generatingthrustor lugs 46 are generally greater in height at the heel portion 40Aof the support plate 40 than at the midfoot portion 40B thereof. Thisproduces a wedge shape through the heel and midfoot regions 14A, 14B ofthe sole 14 from rear to front, that effectively generates and guides aforward and upward thrust for the user's foot as it moves through heelstrike to midstance phases of the foot's “on the ground” travel.

[0162] Referring to FIGS. 2, 3 and 8, the lower-stretch layer 22 is inthe form of a flexible thin substantially flat stretchable sheet 48 ofresilient elastic material, such as rubber, attached in any suitablemanner, such as by gluing, to a bottom surface 40G of the flat supportplate 40 of the upper thruster layer 20. The lower thrustor layer 24disposed below the flat stretchable sheet 48 of the lower stretch layer22 includes a thrustor plate 50, a thrustor cap 52 and a retainer ring54. The thrustor plate 50 preferably is made of a suitable semi-rigidsemi-flexible thin stiff material, such as fiberglass. The thrustorplate 50 is bonded to the bottom surface of a central portion 48A of thestretchable sheet 48 in alignment with the central hole 42 in thesupport plate 40 of the upper thrustor layer 20. In operative stackedrelationship of the stretchable sheet 48 of the lower stretch layer 22between the stretch-generating thrustor plate 50 of the lower thrustorlayer 24 and the support plate 40 of the upper thrustor layer 20, theperiphery 48B of the central portion 48A of the stretchable sheet 48overlies the peripheral edge 50A of the stretch-generating thrustorplate 50 and underlie the rim 40C of the support plate 40.

[0163] Upon compression of the lower thrustor layer 24 toward the upperthrustor layer 20 from a relaxed condition shown in FIGS. 5 and 6 towarda loaded condition shown in FIGS. 7 and 8, as occurs upon impact of theheel and midfoot regions 14A, 14B of the sole 14 of the shoe 10 with asupport surface during normal activity, the periphery 48B of thestretchable sheet 48 is forcibly stretched by the peripheral edge 50A ofthe thrustor plate 50 upwardly past the rim 40C surrounding the centralhole 42 and into the main central stretch chamber 44. This can occur dueto the fact that the thrustor plate 50 is enough smaller in itsfootprint size than that of the central hole 42 in the support plate 40so as to enable the thrustor plate 50 together with the periphery 48B ofthe central portion 48A of the stretchable sheet 48 stretched over thethrustor plate 50 to move and penetrate upwardly through the centralhole 42 and into the main centrally-located stretch chamber 44, as shownin FIGS. 7 and 8.

[0164] The rigidity of the thrustor plate 50 of the lower thrustor layer24 encourages a stable uniform movement and penetration of the thrustorplate 50 and resultant stretching of the periphery 48B of the centralportion 48A of the stretchable sheet 48 into the main central stretchchamber 44 in response to the application of compressive forces. Thethrustor cap 52 is bonded on the bottom surface 50A of the thrustorplate 50 and preferably is made of a flexible plastic or hard rubber andits thickness partially determines the depth of penetration and lengthof drive or rebound of the thrustor plate 50. The ground engagingsurface 52A of the thrustor cap 52 is generally domed shape and presentsa smaller footprint than that of the thrustor plate 50. The retainerring 54 is preferably made of the same material as the thrustor plate 50and surrounds the thrustor plate 50 and thrustor cap 52. The retainerring 54 is bonded on the bottom surface of the stretchable sheet 48 inalignment with the central hole 42 in the support plate 40 and surroundsthe thrustor plate 50 so as to increase the stretch resistance of thecentral portion 48A of the stretchable sheet 48 and stabilize the lowerthrustor layer 24 in the horizontal plane reducing the potential ofjamming or binding of the thrustor plate 50 as it stretches theperiphery 48B of the central portion 48A of the stretchable sheet 48through the central hole 42 in the flat support plate 40 of the upperthrustor layer 20.

[0165] The above-described centrally-located interactions in the heeland midfoot regions 14A, 14B of the sole 14 between the support plate 40of the upper thrustor layer 20, the flat stretchable sheet of the lowerstretch layer 22 and flat thrustor plate of the lower thrustor layer 24of the heel and midfoot regions 14A, 14B occur concurrently andinterrelatedly with the peripherally-located interactions betweenfootbed layer 16, the flat stretchable body 36 of the upper stretchlayer 18 and the thrustor lugs 46 of the upper thrustor layer 20. Theseinterrelated central and peripheral interactions convert the energyapplied to the heel and midfoot regions 14A, 14B of the sole 14 by thewearer's foot into mechanical stretch. The applied energy is thustemporarily stored in the form of concurrent mechanical stretching ofthe central portion 48A of the lower stretchable sheet 48 of the lowerstretch layer 22 and of the spaced portions 36C of the upper stretchablebody 36 of the upper stretch layer 18 at the respective sites of thecentrally-located and peripherally-located stretch chambers 44, 34. Thestored applied energy is thereafter retrieved in the form of concurrentrebound of the stretched portions 36C of the upper stretchable body 36and the thrustor lugs 46 therewith and of the stretched portion 48A ofthe lower stretchable sheet 48 and the thrustor plate 40 therewith. Theresistance and speed of these stretching and rebound interactions isdetermined and controlled by the size relationship between the retainerring 54 and the rim 40C about the central hole 42 of the support plate49 and between the top ends 46A of the thrustor lugs 46 and thecontinuous interior edges 26D encompassing the slots 30 of thefoundation plate 26. The thickness and elastic qualities preselected forthe lower stretchable sheet 48 of the lower stretch layer 22 and theupper stretchable body 36 of the upper stretch layer 18 influence andmediate the resistance and speed of these interactions. The stretchingand rebound of the lower stretchable sheet 48 also causes a torquing ofthe support plate 40. The torquing can be controlled by the thickness ofthe support plate 40 as well as by the size and thickness of theretainer ring 54.

[0166] Referring to FIG. 3, the midfoot region 14B of the sole 14 of thepresent invention also includes a curved midfoot piece 56 and acompression midfoot piece 58 complementary to the curved midfoot piece56. The midfoot portion 26B of the foundation plate 26 terminates at theforward end 26E which has a generally V-shaped configuration. The curvedmidfoot piece 56 preferably is made of graphite and is provided as acomponent separate from the foundation plate 26. The curved midfootpiece 56 has a configuration which is complementary to and fits with theforward end 26E of the foundation plate 26. The forward end 26E of thefoundation plate 26 cradles the number five metatarsal bone of theforefoot as the curved midfoot piece 56 couples the heel and forefootportions 14A, 14B of the sole 14 so as to load the bones of the forefootin an independent manner. The peripheral profiles of the upper stretchlayer 18 and compression midfoot piece 58 are generally the same asthose of the foundation plate 26 and curved midfoot piece 56.

[0167] Referring now to FIGS. 1, 2 and 9 to 11, the metatarsal and toeregions 14C, 14D of the sole 14 basically include the stackedcombinations of metatarsal and toe articulated plates 60A, 60B,metatarsal and toe foundation plates 62A, 62B, a common metatarsal andtoe stretch layer 64, and metatarsal and toe thrustor layers 65A, 65B.The metatarsal and toe thrustor layers 65A, 65B include metatarsal andtoe plates 66A, 66B, metatarsal and toe thrustor caps 68A, 68B andmetatarsal and toe retainer rings 70A, 70B. Except for a common stretchlayer 64 serving both metatarsal and toe regions 14C, 14D of the sole14, there is one stacked combination of components in the metatarsalregion 14C of the sole 14 that underlies the five metatarsals of thewearer's foot and another separate stacked combination of components inthe toe region 14D of the sole 14 that underlies the five toes of thewearer's foot. Except for the upper articulated plates 60A, 60B, theabove-mentioned stacked combinations of components of the metatarsal andtoe regions 14C, 14D of the sole 14 interact (stretching and rebound)generally similarly to the above-described interaction (stretching andrebound) of the stacked combination of components of the heel andmidfoot regions 14A, 14B of the sole 14. However, whereas the stackedcombination of components of the heel and midfoot regions 14A, 14Bprovide interrelated main and peripheral sites for temporary storage andretrieval of the applied energy, the stacked combination of componentsof the metatarsal and toe regions 14C, 14D provide a plurality ofrelatively independent sites for temporary storage and retrieval of theapplied energy at the individual metatarsals and toes of the wearer isfoot. The additional components, namely, the articulated plates 60A,60B, of the metatarsalland toe regions 14C, 14D each has a plurality oflaterally spaced slits 72A, 72B formed therein extending from theforward edges 74A, 74B rearwardly to about midway between the forwardedges 74A, 74B and rearward edges 76A, 76B of the articulated plates60A, 60B. These pluralities of spaced slits 72A, 72B define independentdeflectable or articulatable appendages 78A, 78B on the metatarsal andtoe articulated plates 60A, 60B that correspond to the individualmetatarsals and toes of the wearer's foot and overlie and augment theindependent characteristic of the respective sites of temporary storageand retrieval of the applied energy at the individual metatarsals andtoes of the wearer's foot.

[0168] More particularly, the metatarsal and toe articulated plates 60A,60B are substantially flat and made of a suitable semi-rigidsemi-flexible thin stiff material, such as graphite, while themetatarsal and toe foundation plates 62A, 62B disposed below themetatarsal and toe articulated plates 60A, 60B are substantially flatand made of a incompressible flexible material, such as plastic. Each ofthe metatarsal and toe foundation plates 62A, 62B has a continuousinterior edge 80A, 80B defining a plurality of interconnected interiorslots 82A, 82B which are matched to the metatarsals and toes of thewearer's foot. The continuous interior edges 80A, 80B are spacedinwardly from located inwardly from the peripheries 84A, 84B of themetatarsal and toe foundation plates 62A, 62B so as to leave continuoussolid narrow borders 86A, 86B respectively adjacent to the peripheries84A, 84B. The metatarsal and toe portions of the borders 86A, 86Bencompassing or outlining the locations of the separate metatarsals andtoes of the wearer's foot and of the appendages 78A, 78B on thearticulated plates 60A, 60B are also separated by narrow slits 88A, 88B.The pluralities of interconnected interior slots 82A, 82B definecorresponding pluralities of metatarsal and toe stretch chambers 90A,90B in the respective metatarsal and toe foundation plates 62A, 62B.

[0169] The common metatarsal and toe stretch layer 64 is made of asuitable elastic stretchable material, such as rubber, and is disposedbelow the metatarsal and toe foundation plates 62A, 62B. The peripheralprofile of the common stretch layer 64 generally matches the peripheralprofiles of the articulated plates 60A, 60B and of the foundation plates62A, 62B so as to provide the sole 14 with a common profile when thesecomponents are in an operative stacked relationship with one on top ofthe other. The common stretch layer 64 is attached at its upper surface64A to the respective continuous borders 86A, 96B of the foundationplates 62A, 62B between their respective continuous interior edges 80A,80B and peripheries 84A, 84B.

[0170] The metatarsal and toe thrustor plates 66A, 66B are disposedbelow and aligned with the common stretch layer 64 and the pluralitiesof interconnected interior slots 82A, 82B in foundation plates 62A, 62Bforming the metatarsal and toe stretch chambers 90A, 90B. The metatarsaland toe thrustor plates 66A, 66B are made of semi-rigid semi-flexiblethin stiff material, such as fiberglass. The metatarsal and toe thrustorplates 66A, 66B are bonded to the lower surface 64B of the commonstretch layer 64 in alignment with the pluralities of interconnectedinterior slots 82A, 82B of forming the metatarsal and toe stretchchambers 90A, 90B of the foundation plates 62A, 62B. In the operativestacked relationship of the common stretch layer 64 between thestretch-generating metatarsal and toe thrustor plates 66A, 66B and therespective metatarsal and toe foundation plates 62A, 62B, portions 92A,92B of the common stretch layer 64 overlie the peripheral edges 94A, 94Bof the metatarsal and toe thrustor plates 66A, 66B and underlie thecontinuous interior edges 80A, 80B of the metatarsal and toe foundationplates 62A, 62B.

[0171] Upon compression of the lower metatarsal and toe thrustor plates66A, 66B toward the upper metatarsal and toe foundation plates 62A, 62Bfrom a relaxed condition shown in FIG. 10 toward a loaded conditionshown in FIG. 11, as occurs upon impact of the metatarsal and toeregions 14C, 14D of the sole 14 of the shoe 10 with a support surfaceduring normal activity, the portions 92A, 92B of the common stretchlayer 64 are forcibly stretched by the peripheries 94A, 94B of themetatarsal and toe thrustor plates 66A, 66B upwardly past the continuousinterior edges 80A, 80B of the metatarsal and toe foundation plates 62A,62B into the metatarsal and toe stretch chambers 90A, 90B. This canoccur due to the fact that the metatarsal and toe thrustor plates 66A,66B are enough smaller in their respective footprint sizes than thesizes of the slots 82A, 82B in the metatarsal and toe foundation plates62A, 62B so as to enable the metatarsal and toe thrustor plates 66A, 66Btogether with the portions 92A, 92B of the common stretch layer 64stretched over the respective thrustor plates 66A, 66B to move andpenetrate upwardly through the slots 82A, 82B and into the metatarsaland toe stretch chambers 90A, 90B, as shown in FIG. 11.

[0172] The rigidity of the metatarsal and toe thrustor plates 66A, 66Bencourages a stable uniform movement and penetration of the thrustorplates 66A, 66B and resultant stretching of the portions 92A, 92B of thecommon stretch layer 64 into the metatarsal and toe stretch chambers90A, 90B in response to the application of compressive forces. Themetatarsal and toe thrustor caps 68A, 68B are bonded respectively on thebottom surfaces 96A, 96B of the metatarsal and toe thrustor plates 66A,66B and preferably is made of a flexible plastic or hard rubber andtheir respective thicknesses partially determine the depth ofpenetration and length of drive or rebound of the metatarsal and toethrustor plates 66A, 66B. The metatarsal and toe retainer rings 70A, 70Bare preferably made of the same material as the metatarsal and toethrustor plates 66A, 66B and surround the respective thrustor plates66A, 66B and thrustor caps 68A, 68B. The metatarsal and toe retainerrings 70A, 70B are bonded on the lower surface 64B of the common stretchlayer 64 in alignment with the interior slots 82A, 82B and surround thethrustor plates 66A, 66B so as to increase the stretch resistance of theportion 92A, 92B of the common stretch layer 64 and stabilize themetatarsal and toe thrustor plates 66A, 66B in the horizontal planereducing the potential of jamming or binding of the thrustor plates 66A,66B as they stretch the peripheries of the portions 92a, 92B of thecommon stretch layer 64 into the metatarsal and toe stretch chambers90A, 90 b in the metatarsal and toe foundation plates 62A, 62B.

[0173] The above-described plurality of stretching interactions betweenthe metatarsal and toe foundation plates 62A, 62B, common stretch layer64 and metatarsal and toe thrustor plates 66A, 66B of the metatarsal andtoe regions 14C, 14D in their stacked relationship converts the energyapplied to the metatarsals and toes by the wearer's foot into mechanicalstretch. The applied energy is stored in the form of mechanicalstretching of the metatarsal and toe portions 92A, 92B of the commonstretch layer 64 at the respective sites of the metatarsal and toestretch chambers 90A, 90B. The applied energy is retrieved in the formof rebound of the stretched portions 92A, 92B of the common stretchlayer 64 and the thrustor plates 66A, 66 b therewith. The resistance andspeed of these stretching interactions is determined and controlled bythe size relationship between the retainer rings 70A, 70B and thecontinuous interior edges 80A, 80B in the metatarsal and toe foundationplates 62A, 62B. The thickness and elastic qualities preselected for thecommon stretch layer 64 influence and mediate the resistance and speedof these interactions. The peripheral profiles of the metatarsal and toethrustor plates 66A, 66B are generally the same. The previouslydescribed midfoot pieces 56, 58 also provide a bridge between thecomponents of the heel and midfoot regions 14A, 14B of the sole 14 andthe components of the metatarsal and toe regions 14C, 14D of the sole14.

[0174] The metatarsal and toe regions 14C and 14D of the first preferredembodiment significantly improve the Snow tipping problem by employingmetatarsal and toe thrustor layers with a single torsion armature. Asshown in FIG. 9, the thrustor plates 66A and 66B and the thrustor caps68A and 68B each preferably include an armature 69 extending between thelateral sides of the foot. This single torsion armature therebyinterconnects the actuator elements of the plates 66A, 66B and caps 68A,68B, to give the plates or caps the ability to conduct energy laterallyto medially across the forefoot and toes across individual actuatorelements corresponding to each of the bones of the toe or metatarsalregion. This provides superior guidance and synergism between theactuator elements, as well as the opportunity to provide specificleverage points for the bony structure of the foot.

[0175] Further control over lateral to medial movement can beaccomplished by increasing the height of the lateral and medial bordersof the plates 66A, 66B and caps 68A, 68B. Raising the outer edges guidesthe foot's natural lateral to medial movement.

[0176] Preliminary experimental treadmill comparative testing of askilled runner wearing prototype footwear 10 having soles 14 constructedin accordance with the present invention with the same runner wearingpremium quality conventional footwear, has demonstrated a significantlyimproved performance of the runner while wearing the prototype footwearin terms of the runner's oxygen intake requirements. The prototypefootwear 10 compared to the conventional footwear allowed the runner touse from ten to twenty percent less oxygen running at the same treadmillspeed. The dramatically reduced oxygen intake requirement can only beattributed to an equally dramatic improvement of the energy efficiencythat the runner experienced while wearing the footwear 10 having theheel construction of the present invention. It is reasonable to expectthat this dramatic improvement in energy efficiency will translate intodramatic improvement in runner performance as should be reflected inelapsed times recorded in running competitions.

Second Exemplary Embodiment

[0177] In a second exemplary embodiment, the present invention isdirected to articles of footwear incorporating a sole either as anintegral part thereof or as an insert wherein the sole is constructed soas to absorb, store and release energy during active use. Thus, itshould be appreciated that the invention includes such a sole, whetheralone, as an insert for an existing article of footwear or incorporatedas an improvement into an article of footwear. In any event, the sole isadapted to be worn on the foot of a person while traversing along asupport surface and is operative to store and release energy resultingfrom compressive forces between the person and the support surface.

[0178] With reference first to FIGS. 12-14, the second exemplaryembodiment of the present invention is shown to illustrate its mostsimple construction. As may be seen in FIG. 1, an article of footwear inthe form of an athletic shoe 110 has an upper 112 and a sole 114. Sole114 includes a heel portion 16 that is constructed according to thesecond exemplary embodiment of the present invention.

[0179] The structure of heel portion 116 is best shown with reference toFIGS. 13, 14A and 14B. In these FIGS., it may be seen that heel portion16 includes a first profile in the form of a heel piece 118 that isformed of a relatively stiff material such as rubber, polymer, plasticor similar material. Heel piece 118 includes a first profile chamber 120centrally located therein with first profile chamber 120 being oval inconfiguration and centered about axis “A”. A second profile 122 isstructured as a flat panel 124 that is provided with a primary actuator126 that is similarly shaped but slightly smaller in dimension thenfirst profile chamber 120. Second profile piece 122 is also formed of astiff material, such as rubber, polymer, plastic or similar material.Actuator 126 can be formed integrally with flat panel 124 or,alternatively, affixed centrally thereon in any convenient manner.

[0180] The first layer 128 of a stretchable resilient material isinterposed between heel piece 118 and second profile piece 122 so thatresilient layer 128 spans across first profile chamber 120. To this end,it may be appreciated that heel piece 118 is positioned on a first side130 of first resilient layer 128 while the second profile piece 122 ispositioned on a second side 132 of first resilient layer 128 withactuator 126 facing the second side thereof. Moreover, it may be seenthat first profile chamber 120 has a first interior region 134 that issized to receive actuator 126.

[0181] With reference to FIGS. 14A and 14B, it may be seen that heelpiece 118 and second profile piece 122 are positioned so that acompressive force between the first and the support surface 136 in thedirection of vector “F” moves heel piece 118 and second profile piece122 toward one another. During this movement, the primary actuatorelement 126 advances into the first profile chamber 120. As thishappens, resilient layer 128 is stretched into the first interior region134 to define the active state shown in FIG. 14B. In the active state,energy is stored by the stretching of resilient layer 128. However, whenthe compressive force is removed, resilient layer 128 operates torelease the energy thereby to move heel piece 118 and second profilepiece 122 apart from one another to return them to the static stageshown in FIG. 14A. Accordingly, in operation, when a user places weighton the heel portion 116, either from walking, running or jumping, theimpact force is cushioned and absorbed by the stretching of resilientlayer 128. When the user transfers weight away from heel portion 116,this energy is released thereby helping propel the user in his/heractivity.

Third Exemplary Embodiment

[0182] The simple structure shown in FIGS. 12-14 can be expanded to makea highly active sole, such as that shown in the third exemplaryembodiment of the FIGS. 15-22. With reference to FIG. 15, it may be seenthat an article of footwear in the form of an athletic shoe 150 has anupper 152 and a sole 154 with sole 154 being constructed according tothe third exemplary embodiment of the present invention. Sole 154includes a heel portion 156, a metatarsal portion 158 and a toe portion160, all described below in greater detail. Thus, when reference is madeto a “sole” it may be just one of these portions, a group of portions ora piece that underlies the entire foot or a portion thereof.

[0183] Turning first, then, to heel portion 156, the structure of thesame may best be shown with reference to FIGS. 17-19. In these figures,it may be seen that heel portion 156 includes a first profile 162 formedby an annular heel plate 164 that has a plurality of spaced apartauxiliary actuator elements 166 positioned around the perimeter.Actuator elements 166 are formed of a stiff, fairly rigid material anddefine a first profile chamber 168 which has an opening 170 formed inannular heel plate 164. A layer of resilient stretchable material 172 isconfigured so that it will span across opening 170 with heel plate 164and resilient layer 172 being secured together such as by an adhesive orother suitable means. Thus, first profile piece 162 is positioned on oneside of resilient layer 172, and a second profile piece 174 ispositioned on a second side of resilient layer 172 and is affixedthereto in any convenient manner. Second profile piece 174 is in theform of a heel piece but defines a primary actuator element forinteraction with chamber 170. Thus, when used in this application, thephrase “second profile including a primary actuator element” can meaneither that a second profile is provided with an independent actuatorelement or that the profile itself forms such actuator element.

[0184] In any event, it may further be appreciated that second profilepiece 174 has a second profile chamber 176 formed centrally therein withsecond profile chamber 176 being an elongated six-lobed opening. Heelportion 156 then includes a third profile piece 178 that is providedwith a plunger element 180 that is geometrically similar in shape tosecond profile chamber 176 but that is slightly smaller in dimension.Third profile piece 178 also includes a plurality of openings 182 thatare sized and oriented to receive secondary actuator elements 166 notedabove. To this end, also, heel portion 156 includes a second resilientlayer 184 which has an elongated oval opening 186 centrally locatedtherein. Openings 182 define third profile chambers each having a thirdinterior region.

[0185] With reference now to FIGS. 18 and 19A, it may be understoodthat, when nested, the various pieces which make up heel portion 156form a highly active system for storing energy. Here, it may be seenthat plunger 180 of a selected height so that, when nested, surface 188of plunger 180 contacts the second side 190 of resilient layer 172.Simultaneously, upper surfaces 192 of secondary actuators 166 justcontact surface 194 of second resilient layer 184. Each of secondaryactuator elements 166 align with a respective opening 182 with openings182 having a similar shape as the configuration of actuator 166 butslightly larger in dimension. Second profile piece 174 is then alignedso that second profile chamber 176 is positioned to receive plunger 180when second profile piece 174 moves into the interior region of firstprofile chamber 168.

[0186] This movement, from the static state shown in FIG. 19A isdepicted in the active state of FIG. 19B. Here it may be seen thatresilient layer 172 is forced to undergo a dual stretching wherein firstprofile piece 162, second profile piece 174 and plunger 180 counteractin a dual piston-like action. Resilient layer 172 is accordinglystretched both into first profile chamber 168 (by second profile piece174) and into the interior region of second profile chamber 176 (byplunger 180).

[0187] At the same time, second resilient layer 184 undergoes a singledeflection into each of the third profile chambers formed by openings182. It should now be appreciated that by making the third profilechambers small in vertical dimension, the undersurface 153 of upper 152provides a limit stop so that peripheral support is attained by secondactuator elements 166 while the primary energy storing occurs with thecoaction of plunger 180 and second profile piece 174 on resilient layer172. To further assist in lateral stability, auxiliary positioningblocks 196 may be employed along with optional soft lugs 198 whichextend downwardly between third profile piece 178 and second resilientlayer 184. Moreover, optional metatarsal support plates 200 may beemployed if desired.

[0188] With reference again to FIG. 15, it may be seen that sole 154 isconstructed so as to be oriented at a slight acute angle “a” relative tosupport surface “s” when in the static state, with heel portion 156being elevated relative to toe portion 160. Preferably angle “a” is in arange of about 2 degrees to 6 degrees. By providing this small angle,the release of the energy from the active state is not simply in thevertical direction during mid-stance to toe-off. Rather, since sole 154pivots about the toe portion 160, the restorative force therefore isangled slightly forwardly during this movement. This results in acomponent of the restorative force being transferred to propel the userin a forward direction.

[0189] With reference now to FIGS. 20 and 21, the construction of toeportion 160 may be seen in greater detail. Here, it may be seen that toeportion 160 is formed by a first profile piece 208 that includes a firstprofile by an upstanding perimeter wall 212 that extends around theperipheral edge of first profile piece 208. As may be seen withreference to FIG. 20A, perimeter wall 212 is configured so that chamber210 has five regions 216-220, that correspond to each of the human toes.A first resilient layer 222 is shown in FIG. 20B and has a peripheraledge that is geometrically congruent to first profile piece 208. Whenassembled, first resilient layer 222 spans across first profile chamber210. The structure of toe portion 160 is completed with the addition ofsecond profile piece 224 which is shown in FIG. 20A. Second profilepiece 224 is shaped geometrically similar to the interior side wall 213of perimeter wall 212 so that it can nest in close-fitted, matedrelation into first profile chamber 210. Second profile piece 224 isprovided with openings 226-229 that define second profile chambers whichcorrespond to toe regions 216-219. With reference again to FIG. 20A, itmay be seen that each of these toe regions is provided with anupstanding plunger 236-239 which are sized for mated insertion intoopenings 226-229, respectively.

[0190] Accordingly, as is shown in FIGS. 21A and 21B, toe portion 160provides a dual acting energy storing system. When first profile piece208 and second profile piece 224 are moved from the static state shownin FIG. 21A to the active state shown in FIG. 21B, resilient layer 222undergoes a double deflection. Second profile piece 224, which definesthe primary actuator, moves into first profile chamber 210 thusstretching resilient layer 222 into the interior region thereof.Simultaneously, each of the plungers 236-239 move into the correspondingopening 226-229 in second profile piece 224 thus stretching resilientlayer 222 into the interior region of openings 226-229.

[0191] For ease of manufacture, it is possible to provide plungers236-239 as part of resilient layer 222. Accordingly, this alternativestructure is shown in FIG. 20D wherein resilient layer 222 is shown tohave plunger elements 236′-239′ formed integrally therewith. In FIG.20D, the opposite side of resilient layer of 222′ is revealed from thatshown in FIG. 20B.

[0192] The structure of metatarsal portion 158 is similar to that of toeportion 160. In FIGS. 22A-22C, it may be seen that metatarsal portion158 is formed by a first profile piece 218 that includes a first profilechamber 250 formed therein. First profile chamber 250 is thus bounded byan upstanding perimeter wall 252 that extends around the peripheral edgeof first profile piece 208. As may be seen with reference to FIG. 20A,perimeter wall 252 is configured so that chamber 250 has five regions255-259, that correspond to each of the metatarsal bones. A firstresilient layer 262 is shown in FIG. 22B and has a peripheral edge thatis geometrically congruent to first profile piece 248. When assembled,first resilient layer 262 spans across first profile chamber 250. Thestructure of metatarsal portion 158 is completed with the addition ofsecond profile piece 264 which is shown in FIG. 22C.

[0193] Second profile piece 264 is shaped geometrically similar to theinterior side wall 253 of perimeter wall 252 so that it can nest inclose-fitted, mated relation into first profile chamber 250. Secondprofile piece 264 is provided with openings 265-270 that define secondprofile chambers. With reference again to FIG. 22A, it may be seen thatfirst profile chamber 250 is provided with upstanding plungers 275-280which are sized for mated insertion into openings 265-270, respectively.Plungers 275-280 are oriented to extend between the metatarsal bones ofthe human foot.

[0194] Here again when first profile piece 248 and second profile piece264 move from the static state to the active state, resilient layer 262undergoes a double deflection. Second profile piece 264 which definesthe primary actuator, moves into first profile chamber 250 thusstretching resilient layer 262 into the interior region thereof.Simultaneously, each of the plungers 275-280 move into the correspondingchambers 265-270 in second profile piece 264 thus stretching resilientlayer 262 into the interior region of openings 265-270. The action,therefore, is identical to that described with reference to FIGS. 21Aand 21B.

[0195] The energy focal points for the toe profile piece 224 and theforefoot profile piece 264 center around the chambers 226-229 and265-270, respectively. These chambers are further stabilized by fore andaft torsion armatures which interconnect the actuator portions ofactuators 224 and 264 and conduct energy laterally and medially acrossthe forefoot and toe regions. As shown in FIG. 20C, a fore torsionarmature 230 bounds the fore portion of the profile piece 224, and anaft torsion armature 232 bounds the aft portion of the profile piece224. Similarly, as shown in FIG. 22C, a fore torsion armature 272 boundsthe fore portion of the profile piece 264, and an aft torsion armature274 bounds the aft portion of the profile piece 274.

Fourth Exemplary Embodiment

[0196] A fourth exemplary embodiment of the present invention is shownin FIGS. 23-27. In these FIGS. a sole insert 310 is shown to include anupper 312 and a sole 314. Sole 314 includes a heel section 316, ametatarsal 318 and a toe portion 320. The structure of heel portion 216is best shown in FIGS. 24 and 27A and 27B. Heel portion 316 includes afirst profile piece 322 structured generally as flat plate 323 that hasa plurality of first profile chambers 324 formed therein. Chambers 324are formed as cavities in plate 323. Alternatively, chambers 324 couldbe formed by openings completely through plate 323. A second profilepiece 326 includes a plurality of actuator elements 328 which are sizedfor engagement into the interior region of a respective chamber 324.First profile piece 324 and second profile piece 326 sandwich aresilient layer 330 therebetween so that, when compression forces areexerted, actuator elements 328 are advanced into first profile chamber324.

[0197] Toe portion 320 is formed by a first profile piece 344 and asecond profile piece 346 that defines an actuator. The structure ofprofile pieces 344 and 346 are identical to that described with respectto profile pieces 208 and 224, respectively, so that this description isnot repeated. Similarly, metatarsal portion 318 is formed by a firstprofile piece 354 and a second profile piece 356 with the structure ofprofile pieces 354 and 356 being the same as that of profile pieces 348and 364. One difference that may be noted in the structure of the soleinsert 310, however, is that the resilient layer 330 is a commonresilient layer that extends along the complete sole of insert 310 sothat resilient layer 330 provides the resilient layers for storingenergy in each of heel portion 316, metatarsal portion 318 and toeportion 320.

Fifth Exemplary Embodiment

[0198] FIGS. 28-30 illustrate a fifth exemplary embodiment of the soleof the present invention. This embodiment is similar to the thirdexemplary embodiment described above, with one difference being that theheel portion 456 does not have the optional soft lugs 198 shown in FIG.17 above. Toe portion 460 and metatarsal portion 458, shown in a bottomview in FIG. 30, are substantially the same as shown in 20A-20C and22A-22C, respectively, using like numerals in the 400 series rather thanthe 200 series.

[0199]FIGS. 28 and 29 show the heel portion 456 in an explodedperspective view and an exploded partial cross-sectional view,respectively. The heel portion 456 includes a first profile 462 formedby an annular heel plate 464 that has a plurality of spaced apartauxiliary actuator elements 466 positioned around the perimeter in aU-shape. Actuator elements 466 are formed of a stiff, fairly rigidmaterial and define a first profile chamber 468 which has an opening 470formed in annular heel plate 464. Actuator elements 466 are preferablytapered, as shown in FIG. 29, toward the front of the sole, to provideadditional support toward the rear of the foot. A layer of resilientstretchable material 472 is configured so that it will span acrossopening 470 with heel plate 464 and resilient layer 472 being securedtogether such as by an adhesive or other suitable means. Thus, firstprofile piece 462 is positioned on one side of resilient layer 472, anda second profile piece 474 is positioned on a second side of resilientlayer 472 and is affixed thereto in any convenient manner. Secondprofile piece 474 is in the form of a heel piece but defines a primaryactuator element for interaction with chamber 470.

[0200] It may further be appreciated that second profile piece 474 has asecond profile chamber 476 formed centrally therein with second profilechamber 476 being an elongated six-lobed opening. Heel portion 456 thenincludes a third profile piece 478 that is provided with a plungerelement 480 that is geometrically similar in shape to second profilechamber 476 but that is slightly smaller in dimension. Third profilepiece 478 also includes a plurality of openings 482 that are sized andoriented to receive secondary actuator elements 466 noted above. To thisend, also, heel portion 456 includes a second resilient layer 484 whichhas an elongated oval opening 486 centrally located therein. Openings482 define third profile chambers each having a third interior region.

[0201] To assist in lateral stability, auxiliary positioning blocks 496are provided between the second resilient layer 484 and first profilepiece 464. Additional support blocks or motion control posts 502 areprovided beneath the first profile piece substantially underlying theforward pair of secondary actuator elements 466. The tripodconfiguration of the support blocks 502 and second profile piece 474provides improved stability. The unit is capable of storing energiesderived from rotational forces, producing optimal vertical vectors.Shoes requiring additional stability can take advantage of the abilityto space the motion control posts further apart. For individuals havingflat feet or requiring full support of the midfoot region, an optionalactive foot bridge is contemplated.

[0202] It should be understood that, when nested, the various pieceswhich make up heel portion 456 form a highly active system for storingenergy. In particular, the heel portion 456 exhibits substantiallysimilar behavior as the heel portion 156 depicted in FIGS. 19A and 19B.

[0203] The bottom view of the sole portion shown in FIG. 30 depicts thearrangement of the heel portion 456, metatarsal portion 458 and toeportion 460 comprising the exemplary sole of the shoe. FIG. 30 alsodepicts an additional metatarsal support portion 500, shown moreparticularly in FIGS. 31A-31C. As shown in FIG. 31A, the metatarsalsupport portion 500 is formed by a first profile piece 504 that includesa first profile chamber 510 defined by an upstanding perimeter wall 512that extends around the peripheral edge of first profile piece 504. Aresilient layer 506 is shown in FIG. 31B and has a peripheral edge thatis geometrically congruent to first profile piece 504. When assembled,resilient layer 506 spans across profile chamber 510. The structure ofmetatarsal support portion 500 is completed with the addition of secondprofile piece 508 which is shown in FIG. 31C. Second profile piece 508is shaped geometrically similar to the interior side wall 512 of firstprofile piece 504 so that it can nest in close-fitted, mated relationinto profile chamber 510. More particularly, second profile piece 508and chamber 510 are positioned to cradle the first and second metatarsalbones.

Sixth Exemplary Embodiment

[0204]FIGS. 32 and 33 depict an alternative exemplary embodiment of aheel portion 556 for a sole of the present invention. The heel portion556 comprises a main thrustor 574, a first resilient layer 572, a firstprofile layer 562 with actuator elements or satellite thrustors 566thereon, interlocking rubber lugs 598 on a second resilient layer 584,and a second profile layer 578 overlying the resilient layer 584.Additionally auxiliary support blocks 602 are positioned proximal to theresilient layer 572 beneath the profile layer 562.

[0205] The embodiment shown in FIG. 32 is similar to the heel portion156 shown in FIG. 17, with two differences being that the rubber lugs598 are provided beneath the resilient layer 584 instead of the profilepiece 578, and that the embodiment in FIG. 32 does not have a plungersimilar to element 180 in FIG. 17.

[0206] With reference to FIGS. 32 and 33, it may be seen that heelportion 556 includes a first profile 562 formed by an annular heel plate564 that has a plurality of spaced apart auxiliary or satellite actuatorelements 566 positioned around the perimeter in a U-shape. Actuatorelements 566 are formed of a stiff, fairly rigid material and define afirst profile chamber 568 which has an opening 570 formed in annularheel plate 564. A layer of resilient stretchable material 572 isconfigured so that it will span across opening 570 with heel plate 564and resilient layer 572 being secured together such as by an adhesive orother suitable means. Thus, first profile piece 562 is positioned on oneside of resilient layer 572, and a second profile piece 574 ispositioned on a second side of resilient layer 572 and is affixedthereto in any convenient manner. Second profile piece 574 is in theform of a heel piece but defines a primary actuator element or mainthrustor for interaction with chamber 570. As shown in FIG. 33, secondprofile piece 574 preferably decreases or tapers in dimension in adownward direction, and more preferably has a substantially lowerdome-like shape with sloping surfaces. This shape provides improvedlateral support to the heel through three basic phases of foot movementof heel strike, mid stance and toe off.

[0207] Heel portion 556 includes a third profile piece or foundationlayer 578 that includes a plurality of openings 582 that are sized andoriented to receive actuator elements 566 noted above. To this end, heelportion 556 includes a second resilient layer 584. Openings 582 definesecond profile chambers each having a second interior region. The uppersurfaces of actuators 566 just contact the lower surface of secondresilient layer 584. Each of secondary actuator elements 566 align witha respective opening 582 having a similar shape as the configuration ofactuator 566 but slightly larger in dimension.

[0208] A pair of support blocks or motion control posts 602 are providedunderlying the forward pair of actuators 566. Like the second profilepiece 574, these posts 602 are preferably convex downward in shape, andare more preferably dome-like in shape and forwardly sloped to provideimproved lateral stability to the sole.

[0209] The rubber lugs 598 are provided beneath the resilient layer 584to substantially mate and interlock with the actuators 566. Both therubber lugs 598 and the actuators 566 are preferably tapered in aforward direction to allow for a more controlled lateral displacementduring compression. The side walls of lugs 598 and 566 are preferablysloped approximately 3 to 6 degrees. Each of the lugs mirror each otherto provide elastically cradled interaction. The space between the rubberlugs 598 and thrustors 566 is preferably less than about 0.020 inches,to keep particles larger than 0.020 out. Too tight of a seal creates avacuum, slowing the rebound process. The interlock allows a sufficientair flow, particularly during rebound as a too-tight-of-a-seal creates avacuum slowing the rebound process. In anticipation, this design leavesa large space between the motion control posts 602 to allow for the exitof air, water, etc.

[0210] The actuators 566 preferably have a raised nesting pattern tobetter interlock with the rubber lugs 598. The nesting effect creates amore adaptable environment, improving the conversion of energies fromrotational forces to vertical force storage and retrieval. Byspecifically increasing the thickness of the plate 564 near theactuators 566, weight is also reduced. Nesting patterns also act as arelocator and stabilizer for actuators fostering the energy wave tovertical vectors. Nesting patterns increase the sensitivity of the mainthrustor 574 maximizing the length of propulsion or drive of therebounding thrustor. They also provide additional force at the end ofthe thrust cycle; and help keep actuators in place.

[0211] Varying the actuator rigidity increases the amount of controlover the energy “wave” and the neuro-muscular system's sensitivity toit. If the user's foot naturally supinates, that action tends to putexcessive motion control demands on the outer border of the forefoot,metatarsal number five. This excessive undesirable motion issequentially captured by a chambered actuator, such as actuator 574 inthe sixth exemplary embodiment described above, stored and releasedquickly enough that the negative motion itself becomes the energy forsending the foot laterally to medially enhancing neutral planefunctioning. A more rigid chambered actuator resists tipping or divingto the outer lateral or medial borders, thereby stabilizing theinterlocking energy storing process. Further details regarding varyingthe actuator rigidity is described in the seventh exemplary embodimentbelow.

Seventh Exemplary Embodiment

[0212] FIGS. 34-68 illustrate a seventh exemplary embodiment of a soleconstruction according to the present invention. As used throughout thisspecification, the term “sole construction” refers to both a whole or aportion of the sole used to support a human foot. Furthermore, becausethe components described in the seventh exemplary embodiment are similarto many of the components described in the embodiments above, it shouldbe appreciated that the terminology used to describe similar componentsin the above embodiments may be interchangeable with the terminologyused below.

[0213]FIG. 34 illustrates the preferred sole construction in an explodedperspective view, with each of the components shown upside-down. Moreparticularly, the sole construction includes three regions, namely aheel portion 700, a toe portion 800, and a metatarsal or forefootportion 900. Heel portion 700 includes a main thrustor 702, a firstlayer of resilient stretchable material 704, a satellite thrustor layer706, a second layer of resilient stretchable material 708 and afoundation or secondary thrustor layer 710. Toe portion 800 includes anactuator layer 802 and a chamber layer 804. Forefoot or metatarsalportion 900 includes an actuator layer 902 and a chamber layer 904. Eachof the components comprising each portion of the foot is attachedpreferably using chemical bonding during a molding process as would beknown to one skilled in the art. As described herein, the “top” of thesole construction as shown in FIGS. 34-68 is designated as being towardthe secondary thrustor layer 710, and the “bottom” of the soleconstruction is designated as being toward the main thrustor 702.Correspondingly, the heel portion 700 represents the back or rear of thesole construction and the toe portion 800 represents the front of thesole construction.

[0214] As shown in FIGS. 35-38, the main thrustor 702 is preferablytapered downward and has a substantially domed bottom surface 712 (showntoward the top of FIG. 35) which slopes more in the forward direction,thereby providing lateral stability and allowing rotational movement tothe heel bone of the human foot that it substantially directlyunderlies. The main thrustor 702 is substantially oval-shaped, as shownin FIG. 36, being longer in the front-to-rear direction thanside-to-side. As shown in FIGS. 37 and 38, the main thrustor 702includes an upstanding wall 714, extending upwardly away from the bottomsurface and defining a chamber 716 within the main thrustor. Thischamber 716 preferably has a six-lobed shape, similar to thrustor 474 inthe fifth exemplary embodiment described above (see FIG. 30), but isenclosed by bottom surface 712. The wall 714 preferably slopes slightlyoutward as the wall extends away from the surface 712. The main thrustor712 is preferably designed to be slightly tapered toward the front ofthe foot, such that the height of the wall 714 at the rear end 718 ofthe thrustor is larger than the wall at the front end 720 of thethrustor. This design provides additional support to the rear of theheel while accommodating the rolling motion of the heel. In particular,the curved bottom surface 712 allows energy to spread out laterally whenthe sole construction is compressed and allows for more efficientmovement as the sole construction crosses the ground.

[0215] In the illustrated embodiment, the thrustor 702 has a rear wallheight of about 0.324 inches, which decreases to a height of about 0.252inches at the front of the wall 714. In this embodiment, the wall 714 ispreferably sloped about 1.5 degrees. The bottom surface 712 connectingthe walls and defining the bottom of the chamber 716 preferably has athickness of about 0.125 inches. The height of the entire main thrustor702, from the top of the wall 714 to the bottommost point of the surface712 is about 0.536 inches. As shown in FIG. 36, the length of thethrustor 702, as measured along line 37-37, is about 2.101 inches, andthe width of the thrustor 702, as measured along line 38-38, is about1.561 inches. It should be appreciated that these dimensions are merelyexemplary of one embodiment, and numerous variations can be made to thedimensions of the sole construction. The preferred material for thethrustor 702 is a plastic such as Dupont HYTREL®, but other materialsbeing more or less rigid may also be used. When greater rigidity isdesired, for instance, fiberglass may be used.

[0216] FIGS. 39-41 illustrate a first layer of resilient stretchablematerial 704 that is disposed above the main thrustor 702 of the soleconstruction shown in FIG. 34. This layer is preferably made out ofrubber, and has a substantially oval shape similar to but larger infootprint size than that of the main thrustor 702. The layer 704 alsoincludes a tongue 722 extending from the front of the layer 704, and hascorners 724 and 726 at the front of the layer 704.

[0217] As shown in FIGS. 40 and 41, the top surface 728 of the layer 704is preferably planar. The bottom surface 730 of the layer 704 preferablyhas a boundary region 732 which extends around the perimeter of thelayer 704 in a substantially oval shape. Within this boundary region 732is an intermediate region 734 also having a substantially oval shape,the intermediate region having a greater thickness than that of theboundary region. The increase in thickness between boundary region 732and the intermediate region 734 is preferably gradual, thereby providinga sloped surface 736 as shown in FIG. 41. Within the intermediate region734 is a central stretch region 738 that is slightly recessed relativeto the intermediate region 734, and is separated from the intermediateregion by a boundary ring 740. This central stretch region 738 is sizedto have substantially the same shape as the main thrustor 702 describedabove, such that when the sole construction is compressed during awalking or running activity, the thrustor 702 presses against thecentral region 738 causing it to stretch.

[0218] In the illustrated embodiment, the resilient layer 704 has athickness of about 0.06 inches in the boundary region 732, increasing toabout 0.135 inches in the intermediate region 734, and decreasing toabout 0.125 inches in the central stretch region 738. The length of thelayer 704, when measured from the front tip of the tongue 722 to theback of the layer 704, is about 3.793 inches. The width of the layer 704at its widest portion is about 2.742 inches. The length of the layer704, when measured from the corners 724 and 726 to the back of the layer704, is about 3.286 inches. When measured from the back of the layer tothe frontmost edge of the intermediate region 734, this length is about3.098 inches. The width of the boundary region as it extends around theoval shape of the layer varies from about 0.298 inches at the rear ofthe layer to about 0.28 inches at the lateral sides of the layer. Theslope of the surface 736 is preferably about 45°. Again, it should beappreciated that all of these dimensions are merely exemplary of oneparticular embodiment.

[0219] FIGS. 42-44 illustrate the satellite thrustor layer 706 of thesole construction of FIG. 34. As shown in FIGS. 42 and 43, the layer 706comprises an annular heel plate 742 including an opening 744 whichserves as a chamber through which main thrustor 702 and resilient layer704 extend when the assembled sole construction is compressed. Thus, theopening or chamber 744 has a substantially oval shape which is largeenough to contain the main thrustor 702.

[0220] The preferred shape of the heel plate 742 is substantiallyannular, further comprising two extensions 746 and 748 toward the frontof the foot. As shown in FIG. 34, the shape of the extensions 746 and748 depends on whether the sole construction is for a right foot or aleft foot. The design shown in FIG. 34 is for a left foot, andaccordingly, the left extension 748 preferably has a front surface 752which is concave outward while the right extension 746 preferably has afront surface 750 which is convex outward. It will be appreciated, ofcourse, that these shapes will be reversed for a sole construction for aright foot. Simply put, for either foot, the front surface of the innerextension is preferably convex outward and the front surface of theouter extension is preferably concave outward.

[0221] The top side of the layer 706 is preferably provided with aplurality of satellite thrustors 754 arranged substantially in a U-shapearound the layer. As shown in FIG. 44, the top surfaces of thesethrusters 754 are preferably tapered toward the front of the layer, asindicated by angle α. Furthermore, each satellite thrustor 754preferably has a plurality of holes 756 extending partiallytherethrough. The holes 756 serve to reduce the weight of the satellitethrusters. In the preferred,-embodiment, two of the satellite thrustersare provided over the extensions 746 and 748, while four thrustors aredistributed around the opening 744.

[0222] At the front of the layer 706 and extending from the underside ofthe extensions 746 and 748 are support blocks 758 and 760 which arepreferably integrally formed with the layer 706. As shown in FIG. 42,these support blocks preferably have substantially the same shape as theextensions 746 and 748, in that the front surface of the inner supportblock 746 is preferably convex outward, while the front surface of theouter support block 748 is preferably concave outward. As shown in FIG.44, these support blocks are preferably tapered toward the front of thelayer 706, as indicated by angle β, and have front and rear walls thatare preferably sloped.

[0223] As shown in FIGS. 43 and 44, the satellite thrustors 754 andprovided on the upper side of the layer 706 on a raised nesting pattern762. As shown in FIG. 44, the raised nesting pattern 762 createschambers 764 between the satellite thrustors having a substantiallytrapezoidal shape as shown.

[0224] In the illustrated embodiment, the length of the layer 706 fromthe front surface 750 of extension 746 to the rear of the plate 742 isabout 4.902 inches. The length of the oval-shaped opening 744 along itsmajor axis is about 2.352 inches. The width of the layer 706, asmeasured laterally across its widest portion, is about 2.753 inches. Thewidth of the layer, as measured laterally across its narrowest portion,is about 1.776 inches. The satellite thrusters 754 are tapered, as shownin FIG. 44, about 1.58 degrees, as indicated by angle α. The supportblocks 758 and 760 are preferably tapered about 3 degrees, as indicatedby angle β, and have front and rear walls which are sloped about 7degrees. The height of the layer 706 as measured from the underside ofthe plate 742 to the top of the tallest satellite thrustor, as indicatedby plane B in FIG. 44, is about 0.477 inches. The plate 742 itself has athickness of about 0.1 inches at its thinnest point. For the tallestthrustor, the holes 756 as measured from plane B preferably have a depthof about 0.427 inches. The height of the layer 706, as measured from thebottom of the support block 758, as indicated by plane C in FIG. 44 toplane B, is about 0.726 inches. The layer 706, including the satellitethrusters 754, are preferably made of a material similar to the layer702, and in one preferred embodiment, is Dupont HYTREL®.

[0225]FIG. 45-47 illustrates the second layer 708 of resilient material.This layer is preferably made of rubber, and is shaped substantially tocorrespond with the shape of the satellite thrustor layer 706. Moreparticularly, like the layer 706, layer 708 has a substantially annularshape with a substantially oval-shaped opening 766 therein and twoextensions 768 and 770 protruding forward therefrom. The front surfaceof the outer extension 770 is preferably concave outward, while thefront surface of the inner extension 768 is preferably convex outward.

[0226] Disposed around the opening 760 and on the extensions 768 and 770are stretch regions 772 which correspond to the satellite thrustors 754of layer 706. These stretch regions 772 are preferably integrally formedwith the layer 708 and have an increased thickness as shown in FIG. 47as compared to the rest of the layer 708 to give them a raisedconfiguration. The stretch regions 772 are preferably substantiallyrectangular in shape having curved corners to correspond with the shapeof the satellite thrusters. Each of these stretch regions 772 has afootprint size which is larger than that of the satellite thrusters 754in order to allow the satellite thrustors to press through the stretchregions when the sole construction is compressed.

[0227] A plurality of compressible rubber lugs 774 and 776 is alsoprovided around the layer 708, preferably disposed between each of thestretch regions 772. In the preferred embodiment, five lugs 774 areprovided between the six satellite thrusters, with two additional lugs776 provided at the front of layer 708 underlying extensions 768 and770. These rubber lugs 774 and 776 are preferably integrally formed withthe layer 708. More preferably, the lugs 774 and 776 are substantiallyrectangular in shape to conform to the shape of the stretch regions 772.More particularly, the walls of the lugs 774 as between each of thestretch regions are preferably concave inward, as shown in FIG. 47, suchthat they mate with the shape of the stretch regions 772. As shown inFIG. 47, the lugs preferably extend substantially downward away from thelayer 708, and have sloped walls. These lugs are therefore shaped tomate with the chambers 764 of the satellite thrustor layer 706, andprovide energy storage and return when the sole construction iscompressed causing compression of the lugs 774 in the chambers 764. Thelugs 776 at the front of the layer 708 are shaped to correspond with theshape of the extensions 768 and 770.

[0228] As shown in FIG. 46, for the illustrated embodiment the layer 708has a length measured from the back of the layer 708 to the frontsurface of extension 768 of about 5.17 inches. The width of the layer atits widest portion is about 3.102 inches, and at its narrowest portionis about 2.236 inches. The width of the annular portion of layer 708measured from the rear of the layer to the rear of the opening 766 isabout 1.02 inches. The distance from the rear of the layer 708 to thefront of the opening 766 is about 3.138 inches. The width of the openingas measured across its minor axis is about 1.302 inches. The layer 708along its outer edge has a thickness of about 0.05 inches. At the raisedstretch regions 772 the thickness is about 0.120 inches, and at the lugs774 and 776 the thickness is about 0.319 inches. The lugs 774 arepreferably sloped about 7 degrees to mate with the chambers 764.

[0229] The foundation or secondary thrustor layer 710 is shown in FIGS.48-51. The thrustor layer 710 comprises a plate 778 having a pluralityof openings or chambers 780 therein. This plate 778 is shapedsubstantially the same as the resilient layer 708 and satellite thrustorlayer 706, in that it is substantially oval-shaped corresponding to theshape of the heel with two extensions 782 and 784 extending from thefront. The chambers 780 are arranged to correspond with the satellitethrusters 754 of layer 706, which will move into the chambers 780through resilient layer 708 when the sole construction is compressed.Accordingly, chambers 780 have substantially the same footprint shape asthe satellite thrustors 754, but are sized slightly larger toaccommodate the thrusters 754.

[0230] A secondary thrustor 786 is provided on the underside of theplate 778 substantially centered within the chambers 780 and extendingdownward therefrom. This secondary thrustor 786 is positioned such thatwhen the sole construction is assembled, the thrustor 786 extendsthrough the opening 766 in resilient layer 708 and the opening 744 insatellite thrustor layer 706. More particularly, the thrustor 786preferably has a six-lobe shape which corresponds with the six-lobeopening 716 of main thrustor 702. Thus, when the sole construction iscompressed, the secondary thrustor 786 presses against the stretchportion 738 of resilient layer 704 and into the opening 716. As shown inFIGS. 49 and 51, the bottom surface 788 of secondary thrustor 786preferably has a curved or substantially domed shape, and preferablyalso has a pair of holes 790 extending partially therethrough to reducethe weight of the secondary thrustor.

[0231] The layer 710 of the illustrated embodiment shown in FIGS. 48-51preferably has a length measured from the rear of the plate 778 to thefront of extension 782 of about 5.169 inches. The width of the layer 710across its widest portion is preferably about 3.105 inches, and acrossits narrowest portion is about 2.239 inches. The width between the outerlateral sides of extensions 782 and 784 is preferably about 2.689inches. The front pair of chambers 780 preferably each has a length ofabout 1.25 inches and a width of about 0.63 inches. The plate 710preferably has a thickness of about 0.06 inches, and the secondarythrustor preferably has a height as measured from the top side of theplate of about 0.71 inches. The holes 790 in the secondary thrustor eachhas a diameter of about 0.35 inches and a depth of about 0.5 inches. Thelayer 710 is preferably made of a material such as Dupont HYTREL®,although other similar materials may also be used. For instance, whenmore rigidity is required, materials such as fiberglass and graphite mayalso be used.

[0232] FIGS. 52-55 illustrate the toe actuator layer 802 of the soleconstruction of the seventh exemplary embodiment. This layer 802 ispreferably made of rubber, with all of the elements described and shownin FIGS. 52-55 being preferably integrally formed. The layer 802preferably comprises a main resilient portion 806. Provided on the lowerside of the main portion 806 are the toe actuators 808, 810, 812, 814and 816, corresponding to each of the human toes. As shown in FIG. 54,the toe actuators are preferably raised segments below the main portion806. The first through fourth toe actuators 808-814 also containchambers 818, 820, 822 and 824, respectively, within the actuators,which are substantially oval in shape. As shown in FIGS. 54 and 55, thetoe actuator layer is preferably arched. Along the edges of the toeactuator layer 802 are upwardly-oriented walls 826 to contain the toechamber layer 804, described below.

[0233] The illustrated toe actuator layer 802 preferably measures about4.165 inches from side-to-side. The toe actuator layer 802 preferablyhas a width measured from its frontmost point to its rearmost point ofabout 2.449 inches. The main portion 806 of the layer 802 preferably hasa thickness of about 0.12 inches, with the actuators 808-816 having aheight of about 0.12 inches measured from the underside of the mainportion 806. The walls 826 preferably extend about 0.16 inches away fromthe top side of the main portion 806, and are preferably about 0.55inches thick.

[0234] FIGS. 56-59 illustrate the toe chamber layer 804 that correspondswith the toe actuator layer described above. The toe chamber layer 804is also preferably made of Dupont HYTREL®, and is formed having anupstanding perimeter wall 828 that extends around the peripheral edge ofthe layer 804 to define a chamber 830 therein. The toe chamber layer 804is shaped geometrically similar to the toe actuator layer and is alsopreferably arched as shown in FIGS. 58 and 59. As may be seen withreference to FIG. 57, perimeter wall 828 is configured so that chamber830 has five regions 832, 834, 836, 838 and 840, that correspond to eachof the human toes. Plungers 842, 844, 846 and 848 preferably having asubstantially oval shape are provided in each of the first four regions832, 834, 836 and 838, respectively. The plungers are sized to besmaller than the corresponding chambers of layer 802. Similarly, theactuators of the layer 802 press through the main portion 806 into thechamber 830 when compressed. Thus, the toe actuator layer and toechamber layer together provide a dual action energy storage system. Theenergy storage and return characteristics of the toe portion 800 issubstantially as described with respect to FIGS. 20A-20C, above.

[0235] In the illustrated embodiment, the perimeter wall 828 and theplungers 842-848 preferably have a height of about 0.16 inches. Thelayer 804 has a thickness of about 0.03 inches at its thinnest pointwithin chamber 830. The side-to-side length of the layer 804 ispreferably about 4.044 inches and the front-to-rear width of the layerfrom its frontmost to rearmost point is about 2.326 inches.

[0236] The metatarsal or forefoot actuator layer 902 shown in FIGS.60-64 is designed similar to the toe actuator layer 802. Moreparticularly, the layer 902 is preferably made of rubber, with all ofthe elements described and shown in FIGS. 60-64 being preferablyintegrally formed. The layer 902 preferably comprises a main resilientportion 906. Provided below the main portion 904 are the metatarsalactuators 908, 910, 912, 914, 916 and 918. As shown in FIG. 62, themetatarsal actuators are preferably raised segments below the mainportion 904. The metatarsal actuators each contain chambers 920, 922,924, 926, 928 and 930 within the actuators, which are substantially ovalin shape. As shown in FIGS. 62-64, the metatarsal actuator layer ispreferably arched. Along the edges of the metatarsal actuator layer 904are upwardly-oriented walls 932 to contain the metatarsal chamber layer904, described below.

[0237] The illustrated metatarsal actuator layer 902 preferably has alength of about 4.302 inches as measured across the side-to-side expanseof the metatarsals. The metatarsal actuator layer 902 preferably has awidth of about 3.03 inches as measured from the frontmost to rearmostpoint of layer 902. The main portion 906 of the layer 902 preferably hasa thickness of about 0.12 inches, with the actuators 908-918 having aheight of about 0.12 inches measured from the underside of the mainportion 906. The walls 932 preferably extend about 0.16 inches away fromthe top side of the main portion 906, and are preferably about 0.55inches thick.

[0238] FIGS. 65-68 illustrate the metatarsal chamber layer 904 thatcorresponds with the metatarsal actuator layer 902 described above. Themetatarsal chamber layer 904 is also preferably made of Dupont HYTREL®,and is formed having an upstanding perimeter wall 934 that extendsaround the peripheral edge of the layer 904 to define a chamber 936therein. The metatarsal chamber layer is shaped geometrically similar tothe metatarsal actuator layer and is also preferably arched as shown inFIGS. 67 and 68. As may be seen with reference to FIG. 66, perimeterwall 934 is configured so that chamber 936 has six regions 938, 940,942, 944, 946 and 948. Plungers 950, 952, 954, 956, 958 and 960preferably having a substantially oval shape are provided in each of theregions 938-948 in the chamber 936, respectively, which press downwardthrough the main portion 906 of layer 902 into the chambers 920-930 whenthe sole construction is compressed. Accordingly, the plungers 950-960are sized to be smaller than the corresponding chambers 920-930 of layer902. Similarly, the actuators 908-918 of the layer 902 press through themain portion 906 of layer 902 into the chamber 936 when compressed toprovide dual action energy storage and return. This is substantially thesame energy characteristic as described above with respect to FIGS.22A-22C.

[0239] In the illustrated embodiment, the perimeter wall 934 and theplungers 950-960 preferably have a height of about 0.16 inches. Thelayer 904 has a thickness of about 0.03 inches at its thinnest pointwithin chamber 936. The length of the layer 904 is preferably about4.182 inches, with a width of about 2.908 as measured between thefrontmost and rearmost points of the layer 904.

[0240] The sole construction of the embodiments described above ispreferably attached to the underside of an upper of a shoe (not shown).The embodiments described above may further include an outersole ortraction layer chemically bonded to the bottom of the sole constructionfor contact with the ground. FIGS. 69-76 illustrate toe and forefoottraction layers designed for contact with the ground. As shown in FIGS.69-73, the toe traction layer 860 is sized and shaped to conformsubstantially to the shape and size of the toe actuator layer 802.Similarly, the forefoot traction layer 960 is sized and shaped toconform substantially to the shape and size of the forefoot actuatorlayer 902. Each of these traction layers is preferably formed from arubber material, and has lateral and medial borders that areapproximately twice as tall as at its center to encourage foot and anklerotation within the neutral plane. In one embodiment, the tractionlayers have a thickness of about 0.025 to 0.05 inches, with thethickness at the borders being about 0.05 inches and the thickness atthe center being about 0.025 inches. It will be appreciated thattraction layers may be also be provided underneath the heel portion,motion control posts and other portions of the sole construction.Furthermore, it is also contemplated that a single traction layer beprovided underneath the entire sole construction.

[0241] As illustrated above, the actuators of the sole construction mayhave a varying rigidity to improve stability of the foot and toaccommodate the foot's natural rolling motion. As illustrated by theseventh exemplary embodiment, this varying actuator rigidity may beprovided by making the satellite thrustors 754 and secondary thrustor786 out of a more rigid material, such as 80 to 90 durometer DupontHYTREL®, and making the main thrustor 702 out of a less rigid material,such as 40 to 50 durometer Dupont HYTREL®. Similarly, lugs 774 arepreferably made of a less rigid material such as rubber. Thus, the soleconstruction has alternating rigidity which allows for fine tuning theenergy storage and rebound provided by each of the actuators. Actuatorrigidity may also be varied according to the desired use of the shoe.For instance, more compliant actuators may be desired to conform touneven surfaces and for special use applications, such as trail running,golf and hiking. More rigid actuators may be used where greaterperformance is desired, such as for running and sprinting, verticalleaping, basketball, volleyball and tennis. It should therefore beappreciated that numerous possibilities exist for varying the rigidityof the actuators, in addition to varying their size, shape and position,to provide desired performance characteristics.

[0242] Furthermore, the curved shape of the actuators with correspondingcurved chambers provides mechanical advantages to the performance of thesole construction. In particular, a curved actuator surface, whenloaded, is pressured to a flatter state, causing an expansion of itsfootprint size into the stretchable layer. This expansion of theactuator increases the amount of stretching that the stretchable layerexperiences, thereby leading to an increased storage and rebound ofenergy.

Eighth Exemplary Embodiment

[0243] FIGS. 77-144 illustrate an eighth exemplary embodiment of a soleconstruction according to the present invention. FIGS. 145-147illustrate perspective views of a shoe incorporating this soleconstruction. This eighth embodiment is similar to the seventhembodiment described above, but includes additional structure to preventhorizontal displacement of the stretch layers disposed between thethrustors and the chambers. More particularly, it has been found thatthe thrustors can lose cycling efficiency due to horizontal displacementof the rubber layer during natural foot movement. For example, whilerunning on a cinder track it has been found that a runner generallyexperiences a forward scuffing action as the foot applies a slightbraking force upon foot-strike. This action is responsible for ahorizontal displacement of the actuators shearing on the rubber stretchlayer, thereby negatively affecting their linear relationship with therespective stretch chambers. This resulting negative alignment generatesinefficiencies during thrustor unit cycling.

[0244] To overcome this problem, a sole construction 1000 is provided asshown in FIG. 77 having a heel portion 1100, a toe portion 1200 and ametatarsal or forefoot portion 1300. Heel portion 1100 includes a mainthrustor 1102, a first layer of resilient stretchable material 1104, asatellite thrustor layer 1106, a second layer of resilient stretchablematerial 1108 and a foundation or secondary thrustor layer 1110. Toeportion 1200 includes an actuator layer 1202, a layer of resilientstretchable material 1206, and a chamber layer 1204. Forefoot ormetatarsal portion 1300 includes an actuator layer 1302, a layer ofresilient stretchable material 1306, and a chamber layer 1304. A midsole piece 1002 is provided to be placed between the heel, toe andforefoot portions and the shoe upper (not shown). The mid sole piece1002 includes a first portion 1012 to be positioned forward of the toeportion 1200, a second portion 1010 to be positioned between the toeportion 1200 and the forefoot portion 1300, and a third portion 1008 tobe positioned between the forefoot portion 1300 and the heel portion1100. Traction layers 1252, 1354 and 1194 are provided underneath eachof the toe, metatarsal and heel portions 1200, 1300 and 1100,respectively.

[0245] FIGS. 78-82 illustrate more particularly the main thrustor 1102,which in one embodiment is made of impact resistant nylon or othermaterials as described above. As shown in FIGS. 78-82, the main thrustor1102 preferably has a substantially domed bottom surface 1112 (showntoward the left in FIG. 80) which slopes more in the forward direction,thereby providing lateral stability and allowing rotational movement tothe heel bone of the human foot that it substantially directlyunderlies. The main thrustor 1102 is substantially oval-shaped, as shownin FIG. 79, being longer in the front-to-rear direction thanside-to-side. As shown in FIGS. 80 and 81, the main thrustor 1102includes an upstanding wall 1114, extending upwardly away from thebottom surface and defining a chamber 1116 within the main thrustor.This chamber 1116 preferably has a six-lobed shape, similar to thrustor474 in the fifth exemplary embodiment described above (see FIG. 30), butis enclosed by bottom surface 1112. The wall 1114 preferably slopesslightly outward as the wall extends away from the surface 1112. Themain thrustor 1102 is preferably designed to be slightly tapered towardthe front of the foot, such that the height of the wall 1114 at the rearend 1118 of the thrustor is larger than the wall at the front end 1120of the thrustor. This design provides additional support to the rear ofthe heel while accommodating the rolling motion of the heel. Inparticular, the curved bottom surface 1112 allows energy to spread outlaterally when the sole construction is compressed and allows for moreefficient movement as the sole construction crosses the ground.

[0246] FIGS. 83-86 illustrate a first layer of resilient stretchablematerial 1104 that is disposed above the main thrustor 1102 of the soleconstruction shown in FIG. 77. This layer is preferably made out ofrubber, and has a substantially oval shape similar to but larger infootprint size than that of the main thrustor 1102. The layer 1104 alsoincludes a motion control piece 1122 extending forward from the front ofthe layer 1104, and has corners 1124 and 1126 at the front of the layer1104. The motion control piece 1122, as shown in FIG. 77, preferablyextends downward from the bottom surface 1130 of the layer 1104, therebyproviding additional support to the foot. Moreover, the motion controlpiece includes two opposing posts 1122 a and 1122 b to provide stabilityto the sole construction.

[0247] As shown in FIG. 85, the top surface 1128 of the layer 1104 ispreferably planar. As shown in FIG. 83, the bottom surface 1130 of thelayer 1104 preferably has a first boundary region 1132 which extendsaround the perimeter of the layer 1104 in a substantially oval shape.Within this first boundary region 1132 is a first intermediate region1134 also having a substantially oval shape, the first intermediateregion having a greater thickness than that of the boundary region. Theincrease in thickness between first boundary region 1132 and the firstintermediate region 1134 is preferably gradual, thereby providing asloped surface 1136 as shown in FIG. 86. Within the first intermediateregion 1134 is a second boundary region 1135, and within second boundaryregion is second intermediate region 1137. The central stretch region1138 is located within the second intermediate region 1137 and isslightly recessed relative to the second intermediate region 1137.

[0248] The second boundary region 1135 is sized to have substantiallythe same shape as the main thrustor 1102 described above, such that whenthe sole construction is compressed during a walking or runningactivity, the thrustor 1102 presses against the central region 1138causing it to stretch. Moreover, the second intermediate region 1137preferably has a six-lobe shape generally corresponding to the six-lobesecondary thrustor 1186 described below. This second intermediate region1137 thereby helps guide the secondary thrustor 1186 into the chamber1116 shown in FIG. 81. Moreover, because the second intermediate regionis elevated with respect to the central stretch region 1138, when thesole construction is assembled, the second intermediate region 1137preferably mates within the chamber 1116. Thus, when the thrustor 1186described below is compressed into the chamber 1116, this secondaryintermediate region 1137 helps to prevent horizontal displacement of thelayer 1104.

[0249] Similarly, as the main thrustor 1102 is compressed upwardlyagainst the layer 1104, the first intermediate region 1134, because itis elevated with respect to the second boundary region 1135, effectivelysurrounds the thrustor 1102. This thereby not only guides the thrustoragainst the second boundary region 1135, but it also prevents horizontaldisplacement of the layer 1104.

[0250] FIGS. 87-90 illustrate the satellite thrustor layer 1106 of thesole construction of FIG. 77. This layer is preferably made of plasticsuch as described for the satellite thrustor layers in the embodimentsabove. As shown in FIGS. 87 and 88, the layer 1106 comprises an annularheel plate 1142 including an opening 1144 which serves as a chamberthrough which main thrustor 1102 and resilient layer 1104 extend whenthe assembled sole construction is compressed. Thus, the opening orchamber 1144 has a substantially oval shape which is large enough tocontain the main thrustor 1102.

[0251] The preferred shape of the heel plate 1142 is substantiallyannular, further comprising two extensions 1146 and 11148 toward thefront of the foot. As shown in FIG. 77, the shape of the extensions 1146and 1148 depends on whether the sole construction is for a right foot ora left foot. The design shown in FIG. 77 is for a left foot, andaccordingly, the left extension 1148 preferably has a front surface 1152which is concave outward while the right extension 746 preferably has afront surface 750 which is convex outward. It will be appreciated, ofcourse, that these shapes will be reversed for a sole construction for aright foot. Simply put, for either foot, the front surface of the innerextension is preferably convex outward and the front surface of theouter extension is preferably concave outward.

[0252] The top side of the layer 1106 is preferably provided with aplurality of satellite thrustors 1154 arranged substantially in aU-shape around the layer. As shown in FIGS. 89-90, the top surfaces ofthese thrusters 1154 are preferably tapered toward the front of thelayer, such that the thrustors 1154 are forwardly sloped. Furthermore,each satellite thrustor 1154 preferably has a plurality of holes 1156extending partially therethrough. The holes 1156 serve to reduce theweight of the satellite thrustors. In one preferred embodiment, two ofthe satellite thrustors are provided over the extensions 1146 and 1148,while four thrustors are distributed around the opening 1144.

[0253] At the front of the layer 1106 and extending from the undersideof the extensions 1146 and 1148 are support blocks 1158 and 1160 whichare preferably integrally formed with the layer 1106. As shown in FIG.87, these support blocks preferably have substantially the same shape asthe extensions 1146 and 1148, in that the front surface of the innersupport block 1158 is preferably convex outward, while the front surfaceof the outer support block 1160 is preferably concave outward. As shownin FIG. 89, these support blocks preferably have a sloping surface,tapered to decrease in thickness toward the back of the layer 1106.

[0254] As shown in FIGS. 87-88, the satellite thrustors 1154 areprovided on the upper side of the layer 1106 on a raised nesting pattern1162. As shown in FIG. 88, the raised nesting pattern 1162 createschambers 1164 between the satellite thrusters having a substantiallytrapezoidal shape as shown.

[0255] FIGS. 91-95 illustrate the second layer 1108 of resilientmaterial. This layer is preferably made of rubber, and is shapedsubstantially to correspond with the shape of the satellite thrustorlayer 1106. More particularly, like the layer 1106, layer 1108 has asubstantially annular shape with a substantially oval-shaped opening1166 therein and two extensions 1168 and 1170 protruding forwardtherefrom. The front surface of the outer extension 1770 is preferablyconcave outward, while the front surface of the inner extension 1168 ispreferably convex outward.

[0256] Disposed around the opening 1160 and on the extensions 1168 and1170 are stretch regions 1172 which correspond to the satellitethrustors 1154 of layer 1106. The stretch regions 1172 are preferablysubstantially rectangular in shape having curved corners to correspondwith the shape of the satellite thrusters. Each of these stretch regions1172 has a footprint size which is larger than that of the satellitethrustors 1154 in order to allow the satellite thrustors to pressthrough the stretch regions when the sole construction is compressed.Each of these stretch regions further includes a boundary portion havingan increased thickness to further define and enclose the portion throughwhich the satellite thrustors can extend.

[0257] A plurality of compressible rubber lugs 1174 and 1176 is alsoprovided around the layer 1108, preferably disposed between each of thestretch regions 1172. In the preferred embodiment, five lugs 1174 areprovided between the six satellite thrusters, with two additional lugs1176 provided at the front of layer 1108 underlying extensions 1168 and1170. These rubber lugs 1174 and 1176 are preferably integrally formedwith the layer 1108. More preferably, the lugs 1174 and 1176 aresubstantially rectangular in shape to conform to the shape of thestretch regions 1172. More particularly, the walls of the lugs 1174 asbetween each of the stretch regions are preferably concave inward, asshown in FIG. 92, such that they mate with the shape of the stretchregions 1172. As shown in FIG. 95, the lugs preferably have slopedwalls. These lugs are therefore shaped to mate with the chambers 1164 ofthe satellite thrustor layer -1106, and provide energy storage andreturn when the sole construction is compressed causing compression ofthe lugs 1174 in the chambers 1164. The lugs 1176 at the front of thelayer 1108 are shaped to correspond with the shape of the extensions1168 and 1170.

[0258] Unlike the embodiment of FIGS. 45-47 above, the opening 1166 isnot enclosed at its front portion by the layer 1108. Accordingly,whereas the stretch layer shown in FIG. 46 includes an outer boundarywhich surround the stretch regions 772 and rubber lugs 776 and 778, thestretch layer of FIGS. 91-95 is substantially defined only by thestretch regions 1172 and the lugs 1174 and 1176.

[0259] The foundation or secondary thrustor layer 1110, which ispreferably made of an impact resistant nylon, is shown in FIGS. 96-100.The thrustor layer 1110 comprises a plate 1178 having a plurality ofopenings or chambers 1180 therein. This plate 1178 is shapedsubstantially the same as the resilient layer 1108 and satellitethrustor layer 1106, in that it is substantially oval-shapedcorresponding to the shape of the heel with two extensions 1182 and 1184extending from the front. The chambers 1180 are arranged to correspondwith the satellite thrustors 1154 of layer 1106, which will move intothe chambers 1180 through resilient layer 1108 when the soleconstruction is compressed. Accordingly, chambers 1180 havesubstantially the same footprint shape as the satellite thrustors 1154,but are sized slightly larger to accommodate the thrusters 1154.

[0260] A secondary thrustor 1186 is provided on the underside of theplate 1178 substantially centered within the chambers 1180 and extendingdownward therefrom. This secondary thrustor 1186 is positioned such thatwhen the sole construction is assembled, the thrustor 1186 extendsthrough the opening 1166 in resilient layer 1108 and the opening 1144 insatellite thrustor layer 1106. More particularly, the thrustor 1186preferably has a six-lobe shape which corresponds with the six-lobeopening 1116 of main thrustor 1102. Thus, when the sole construction iscompressed, the secondary thrustor 1186 presses against the stretchportion 1138 of resilient layer 1104 and into the opening 1116. As shownin FIGS. 97 and 98, the bottom surface 1188 of secondary thrustor 1186preferably has a curved or substantially domed shape.

[0261] As shown in FIG. 96, the chambers 1180 of the secondary thrustorlayer 1110 are each preferably surrounded by raised walls 1192 whichextend around the layer 1110 and are shaped to correspond with the shapeof the resilient layer 1108. Thus, when the sole construction isassembled, the layer 1108 preferably nests within the raised walls.Then, when a compressive force is applied to the sole construction, theraised walls 1192 operate to prevent displacement of the chambers 1172.

[0262] FIGS. 101-105 illustrate a traction layer 1194 providedunderneath the heel portion as shown in FIG. 77. More particularly, thistraction layer 1194 is provided beneath the thrustor 1102. The tractionlayer 1194 is preferably made of rubber, and in the embodiment shown inFIGS. 101-105, comprises a plurality of concentric rings provided togive the layer 1194 a substantially dome shape.

[0263] FIGS. 106-109 illustrate the toe actuator layer 1202 of the soleconstruction of the eighth exemplary embodiment. This layer 1202 ispreferably made of rubber, and preferably includes toe actuators 1208,1210, 1212, 1214 and 1216, corresponding to each of the human toes. Thefirst through fourth toe actuators 1208-1214 also contain chambers 1218,1220, 1222 and 1224, respectively, within the actuators, which aresubstantially oval in shape. As shown in FIGS. 108 and 109, the toeactuator layer is preferably arched.

[0264] FIGS. 10-114 illustrate a layer of resilient stretchable material1206 that is provided over the toe actuators as shown in FIG. 77. Thislayer is preferably made of rubber, and has a bottom surface (as viewedin FIG. 77) shown in FIG. 111 which is patterned to correspond to thetoe actuator layer 1202. More particularly, this surface includes aslightly raised wall 1207 which is shaped to correspond with the outerborder of the layer 1202. The bottom surface also includes inner rings1218′, 1220′, 1222′ and 1224′, which are also raised walls whichcorrespond in shape and size to the chambers 1218, 1220, 1222 and 1224.These raised walls assist in seating the toe layer 1202 against theresilient layer 1206, and thereby guide the toe actuator 1202 againstthe resilient layer 1206 during compression of the sole construction,while also preventing horizontal displacement of the resilient layer1206. Similarly, the top surface shown in FIG. 113 also includes raisedwall rings 1242′, 1244′, 1246′ and 1248′ for guiding the plungers 1242,1244, 1246 and 1248, described below.

[0265] FIGS. 115-117 illustrate the toe chamber layer 1204 thatcorresponds with the toe actuator layer described above. The toe chamberlayer 1204 is preferably made of plastic such as described above, and isformed having an upstanding perimeter wall 1228 that extends around theperipheral edge of the layer 1204 to define a chamber 1230 therein. Thetoe chamber layer 1204 is shaped geometrically similar to the toeactuator layer and is also preferably arched as shown in FIG. 117 As maybe seen with reference to FIG. 116, perimeter wall 1228 is configured sothat chamber 1230 has five regions 1232, 1234, 1236, 1238 and 1240, thatcorrespond to each of the human toes. Plungers 1242, 1244, 1246 and 1248preferably having a substantially oval shape are provided in each of thefirst four regions 1232, 1234, 1236 and 1238, respectively. The plungersare sized to be smaller than the corresponding chambers of layer 1202.Similarly, the actuators of the layer 1202 press through the resilientlayer 1206 into the chamber 1230 when compressed. Thus, the toe actuatorlayer and toe chamber layer together provide a dual action energystorage system.

[0266] The toe chamber layer 1204 further includes an inner wall 1250which surrounds the chamber 1230. The shape of this inner wallcorresponds to the shape of the toe actuator layer 1202, such that whena compressive force is applied to the sole construction, the toeactuator layer 1202 moves against the resilient layer 1206 into thechamber as defined by the wall 1250. The resilient layer 1206 preferablysits over the wall 1250, and rests inside perimeter wall 1228. Thus, thewall 1228 substantially encloses the resilient layer 1206, therebypreventing horizontal displacement of the layer 1206 when a compressiveforce is applied to the sole construction.

[0267] FIGS. 118-121 illustrate a rubber toe traction layer 1252 whichis preferably positioned underneath the toe actuator layer 1202 shown inFIG. 77. This traction layer has geometrically substantially the sameconstruction as the toe actuator layer 1202

[0268] The metatarsal or forefoot actuator layer 1302 shown in FIGS.122-125 is designed similar to the toe actuator layer 1202. Moreparticularly, the layer 1302 is preferably made of rubber, and includesmetatarsal actuators 1308, 1310, 1312, 1314, 1316 and 1318. Themetatarsal actuators each contain chambers 1320, 1322, 1324, 1326, 1328and 1330 within the actuators, which are substantially oval in shape. Asshown in FIGS. 124-125, the metatarsal actuator layer is preferablyarched.

[0269] FIGS. 126-130 illustrate a layer of resilient stretchablematerial 1306 that is provided over the metatarsal actuators as shown inFIG. 77. This layer is preferably made of rubber, and has a bottomsurface (as viewed in FIG. 77) shown in FIG. 127 which is patterned tocorrespond to the metatarsal actuator layer 1302. More particularly,this surface includes a slightly raised wall 1307 which is shaped tocorrespond with the outer border of the layer 1302. The bottom surfacealso includes inner rings 1320′, 1322′, 1324′, 1326′, 1328′ and 1330′,which are also raised walls which correspond in shape and size to thechambers 1320, 1322, 1324, 1326, 1328 and 1330. These raised wallsassist in seating the metatarsal layer 1302 against the resilient layer1306, and thereby guide the metatarsal actuator 1302 against theresilient layer 1306 during compression of the sole construction, whilealso preventing horizontal displacement of the resilient layer 1306.Similarly, the top surface shown in FIG. 129 also includes raised wallrings 1350′, 1352′, 1354′, 1356′, 1358′ and 1360′ for guiding theplungers 1350, 1352, 1354, 1356, 1358 and 1360, described below.

[0270] FIGS. 131-133 illustrate the metatarsal chamber layer 1304 thatcorresponds with the metatarsal actuator layer 1302 described above. Themetatarsal chamber layer 1304 is also preferably made of plastic such asdescribed above, and is formed having an upstanding perimeter wall 1334that extends around the peripheral edge of the layer 1304 to define achamber 1336 therein. The metatarsal chamber layer is shapedgeometrically similar to the metatarsal actuator layer and is alsopreferably arched as shown in FIG. 133. As may be seen with reference toFIG. 132, perimeter wall 1334 is configured so that chamber 1336 has sixregions 1338, 1340, 1342, 1344, 1346 and 1348. Plungers 1350, 1352,1354, 1356, 1358 and 1360 preferably having a substantially oval shapeare provided in each of the regions 1338-1348 in the chamber 1336,respectively, which press downward through the resilient layer 1306 intothe chambers 1320-1330 when the sole construction is compressed.Accordingly, the plungers 1350-1360 are sized to be smaller than thecorresponding chambers 1320-1330 of layer 1302. Similarly, the actuators1308-1318 of the layer 1302 press through the resilient layer 1306 intothe chamber 1336 when compressed to provide dual action energy storageand return.

[0271] The metatarsal chamber layer 1304 further includes an inner wall1362 which surrounds the chamber 1336. The shape of this inner wallcorresponds to the shape of the metatarsal actuator layer 1302, suchthat when a compressive force is applied to the sole construction, thetoe actuator layer 1302 moves against the resilient layer 1306 into thechamber as defined by the wall 1362. The resilient layer 1306 preferablysits over the wall 1350, and rests inside perimeter wall 1334. Thus, thewall 1334 substantially encloses the resilient layer 1306, therebypreventing horizontal displacement of the layer 1306 when a compressiveforce is applied to the sole construction.

[0272] FIGS. 134-137 illustrate a rubber metatarsal traction layer 1354which is preferably positioned underneath the metatarsal actuator layer1302 shown in FIG. 77. This traction layer has geometricallysubstantially the same construction as the metatarsal actuator layer1302.

[0273] FIGS. 138-141 illustrate more particularly the mid sole 1002 usedto connect the toe portion heel portion 1100, toe portion 1200 and heelportion 1300 together. The mid sole 1002 is preferably made of expandedEVA or other suitable material. The portions 1008, 1010 are preferablyshaped to fill in the space between the portions 1100, 1200 and 1300,with the portion 1012 preferably defining a curved front tip. In theheel area of the mid sole a center portion 1006 is provided generallycorresponding in size to the main thrustor 1102.

[0274] FIGS. 142-144 illustrate a mid sole traction layer 1014, notshown in FIG.77, which may be used to underly portion 1002 in FIG. 77.This mid sole traction layer 1014 is preferably made of natural gumrubber. It will be appreciated that other traction layers may beprovided over portions of the mid sole.

[0275] The chambered actuators described in the embodiments aboveadvantageously reduce the tipping problem associated with Snow's cleats.For instance, in the toe portion 1200 and metatarsal portion 1300, theplungers provided in the toe chamber layer 1204 and metatarsal chamberlayer 1304, respectively, are preferably centered therein to providefulcrums which create a lever upon which to balance the actuators 1202,1302. Similarly, in the heel portion 1100, the secondary thrustor 1186operates as a lever to prevent tipping of the main thrustor 1194. Moreparticularly, during a walking or running activity, when a leading orfore edge of an actuator is depressed into a corresponding rubber layerand into a chamber, the fulcrum plungers or the secondary thrustorengage the rubber layer supporting the central portion of the actuator,and by moving into a corresponding chamber on the opposite side of therubber layer, cause an upward rocking of the aft edge of the actuator.This action balances the actuator and prevents tipping.

[0276] The movement of the plungers against the rubber layer alsogenerates upward dynamic stretching of the rubber layer. The overalleffect of the actuator and plungers moving against the rubber layerincreases the load experienced by the rubber layer, thereby increasingthe energy response of the layer. The plungers and secondary thrustoralso draw energy from the leading edge of the actuator to the internalchambers of the actuator, thereby assisting in the gathering of lateraland rotational forces and increasing the efficiency of the energystorage and return. Thus, with the chambered actuators described above,the preferred embodiments of the present invention are able to store andreturn more potential energy per actuator cycle.

[0277] Use of Metal Components

[0278] It will be appreciated that for any of the embodiments describedabove, metallic components can be used for any number of the parts. Theuse of metallic components provide added rigidity to various componentsused in the sole construction, which can be advantageous over less rigidparts which can become dented or deformed during use of the soleconstruction.

[0279] For example, any or all of the actuators, actuator layers,thrustors or thrustor layers described above for the heel, toe ormetatarsal sections can be made of a metallic component. Preferredmetals include, but are not limited to, magnesium, titanium, aluminum,steel, and alloys and combinations thereof. Moreover, the chamber layersdescribed above can also be formed of these or other metallic materials.It will be appreciated that any of the components described above aspreferably being formed of a rigid material, such as Dupont HYTREL®, caninstead be formed of these or other metallic materials.

[0280] Experimental Results

[0281] The advantages of Applicant's invention are illustrated in theresults of experimental tests performed on the shoe described inaccordance with the seventh exemplary embodiment of the presentinvention (“Applicant's shoe”), as compared to a standard shoe. Unlessotherwise noted, Mizuno Wave Runner Technology was used for the standardshoe. The results are presented below.

[0282] 1. Whole Body Efficiency Results (VO₂ Uptake Tests)

[0283] Whole body efficiency measures the consumption and expiration ofgases. To determine the improvement of Applicant's shoe as compared tothe standard shoe, graded and steady state exercise tests were performedto analyze the expired gases (determine VO₂) with 3 or 12 leadelectrocardiography during treadmill running on athletes. Specifically,VO₂ measures O₂ delivered by the heart/cardiac output.

[0284] Test subject athletes reported for testing on two occasions. Onthe first occasion each subject wore the standard shoe and VO_(2max) wasdetermined by a graded exercise test on a treadmill. On the secondoccasion the standard shoe and Applicant's shoe were compared using a75-90% VO_(2max) graded steady state intensity and absolute intensityprotocol. The equipment used was a Sensor Medics V_(max) 29 metaboliccart equipped with two calibration gas tanks, one laptop computer withsoftware installed, one printer, one VGA monitor and 12/3 lead EKGmachines. Additionally, sets of flow sensors, tubing, mouthpieces andheadgears, as well as an ample supply of EKG patch electrodes, wereused.

[0285] In response to the same running protocol, Applicant's shoedemonstrated a reduced O₂ consumption at the same relative (80%-90%)VO_(2max) and absolute intensity in all male athletes tested. Thisfinding was notable at intensities representing 80-90% VO_(2max) and atspeeds of 9.5, 10, 10.5 and 11 miles/hr. This finding is consistent withan improved whole body efficiency when running in Applicant's shoerelative to the standard shoe at paces that are typical of thoseperformed during racing and intense recreational training. The averageimprovement in whole body efficiency at the aforementioned intensitieswas 13%. However, at the higher absolute and relative intensities, theaverage improvement in whole body efficiency was 15%. Individualvariability was present, as certain individuals demonstrated an averageimprovement of efficiency of 21% and 18%, respectively, at the sameabsolute intensity of 10, 10.5 and 11 miles/hr. This individualvariation may be credited to initial differences in biomechanics, bodymechanics or running style. Interestingly, the least improvement wasmeasured in the ultradistance runners, whereas the greatest effect ofthe shoe was measured in shorter distance triathletes/duathletes. Thisfinding is consistent with the idea that the ultradistance runnersdemonstrated improved mechanical or biomechanical efficiency initiallywhen compared with the shorter distance cross-trained athlete. Theoverall findings were that every subject received whole body efficiencyimprovements using Applicant's shoe. Results varied between subjects dueto biomechanics, body mechanics and running style. In conclusion,Applicant's shoe leads to improved running efficiency as demonstrated bythe physiological data of all male athletes tested.

[0286] The preliminary data to compare whole body efficiency during likeprotocol treadmill running using Applicant's shoe and the standard shoein a female elite athlete is consistent with data previously collectedon men. Although the magnitude of the effect was less, the measured VO₂was consistently lower at all measured workloads and the discrepancybetween males and one female runner may be credited to different runningmechanics (specifically, forefoot running in the female). To thiseffect, when mechanics were made more similar by an imposed grade duringvery fast treadmill running, the whole body efficiency was improved. Itis likely that the improved whole body efficiency measured in an elitefemale athlete when wearing the experimental is similar to that measuredpreviously in men.

[0287] As seen in male runners, in response to the same runningprotocol, Applicant's shoe demonstrated a reduced 02 consumption at thesame relative (80-90%) VO_(2max) and absolute intensity in an elitefemale runner. This finding was notable at intensities representing(80-95%) VO_(2max) and at speeds of 8.5, 9, 9.5 and 10 mph. This findingis consistent with an improved whole body efficiency when running in theexperimental shoe relative to the standard shoe at paces that aretypical of those performed during racing and intense recreationaltraining. Although the magnitude of the improvement measured atdifferent intensities was smaller than that measured in men, it is stilla notable (around 3%) difference. To this difference, it was noted thatthe elite female athlete landed primarily on her forefoot. Hence, thetotal effectiveness of the shoe may not have been fully measured due tothe construction of the shoe which places the major mechanism in theheel of the shoe. Of interest was the VO₂ measurement during exercise onthe treadmill in response to a change in grade. Mechanically for aforefoot runner this grade change at a 10.5 mph speed may force theathlete to spring off from her heel and thereby explain the improvementin whole body efficiency measured. Specifically, we measured a 5-7%decrease in whole body efficiency in the light of an increase inworkload. Therefore, this improvement in whole body efficiency inresponse to grade is greatly underestimated. On the other hand, thispreliminary data offers insight as to more areas of investigation forthe possibility of improved whole body efficiency due to the mechanicsof the experimental shoe.

[0288] 2. Whole Body Kinematic Test

[0289] Applicant has also performed a whole body kinematic test to showhow the whole body receives benefits from Applicant's invention inparticular, by providing more proper angles at the ankle, knee and hipand less vertical body movements.

[0290] A running stride analysis was performed on the two subjects todetermine running temporal and kinematic parameters across varyingshoes. The shoes tested were as follows: a regular pair of runningshoes, and two pairs of running shoes designed to return energy to therunner (“Applicant's shoe”). The concept behind Applicant's shoe is thatit absorbs the energy of impact with the ground and is able to transferthat energy back to the runner in the latter phases of stance, thusimproving running economy. It was hypothesized that there would beobservable changes in the running kinematics, notably, decreased stancetime combined with an increased swing time (time in the air) as well asincreased leg extension in late stance as the shoe returned energy.

[0291] Data was collected on one male (Subject 1) and one female(Subject 2). Eighteen joint markers were placed bilaterally on thefollowing landmarks: the lateral aspect of the head of the 5^(th)metatarsal, the lateral malleolus, lateral approximation of the axis ofrotation of the knee, lateral approximation of the axis of rotation ofthe hip, iliac crests, lateral approximation of the shoulder axis ofrotation, lateral elbow, wrist, forehead and chin. Subject 1 was filmedwith 3 video cameras at a frame rate of 30 frames per second whilerunning on a treadmill at 10.0 mph (4.47 m/s). The trial order was:regular shoes, energy return shoes, lightweight energy return shoes.Subject 2 was filmed while running at 8.6 mph (3.84 m/s) and 10.0 mph(4.47 m/s). The video data was analyzed using the Ariel PerformanceAnalysis System (APAS) to generate a three-dimensional image of thesubject for each of the three trials. Trial information is providedbelow: Speed Subject Trial (m/s) Shoe 1 1 4.47 Regular 1 2 4.47 EnergyReturn 1 3 4.47 Light Energy Return 2 1 3.84 Regular 2 2 4.47 Regular 23 3.84 Light Energy Return 2 4 4.47 Light Energy Return

[0292] The temporal measure of the running stride were determined to beas follows: TABLE 1 Temporal Stride Measurements Sub- Speed Trial StanceSwing Stride ject (m/s) Number Time(s) Time(s) Rate(s) 1 4.47 1 0.2070.420 0.627 1 4.47 2 0.207 0.426 0.633 1 4.47 3 0.207 0.413 0.620 2 3.841 0.217 0.450 0.667 2 4.47 2 0.206 0.440 0.647 2 3.84 3 0.206 0.4400.647 2 4.47 4 0.203 0.437 0.640

[0293] The general sagittal plane-kinematic variables of stride length,vertical displacement and R foot travel are shown below. Stride lengthwas determined from the stride rate determined above and the treadmillvelocity, which was assumed to remain constant. The verticaldisplacement is the measure of the sagittal plane travel of the foreheadmarker. The travel of the right foot is the measure of the foot'ssagittal displacement through one complete stance and swing cycle. TABLE2 General Kinematic Measurements R Foot travel Stride Vertical duringone Sub- Speed Trial Length Displace- running ject (m/s) Number (m) ment(cm) stride (m) 1 4.47 1 2.80 6.0 1.95 1 4.47 2 2.83 5.8 2.01 1 4.47 32.77 5.0 1.94 2 3.84 1 2.56 6.9 1.91 2 4.47 2 2.89 5.8 2.00 2 3.84 32.48 6.4 1.86 2 4.47 4 2.86 5.8 2.01

[0294] The lower extremity sagittal plane kinematics were determined forthe right side. This included the hip, knee and ankle angles. Hip anglewas calculated as the angle between the thigh and the pelvis and anincreasing angle equals hip extension. Knee angle was calculated as theangle between the thigh and the shank segments and an increasing angleequals extension. Ankle angle was calculated as the angle between theshank and the foot and an increasing angle equals plantarflexion.

[0295] The maximum hip extension was observed just prior to toe off andmaximum hip flexion was observed just prior to heel strike. TABLE 3 HipKinematics Maximum Maximum Range of hip hip motion Sub- Speed Trialextension flexion of the hip ject (m/s) Number (degrees) (degrees)(degrees) 1 4.47 1 171.2 130.4 40.8 1 4.47 2 166.8 128.2 38.6 1 4.47 3171.2 131.0 40.2 2 3.84 1 157.2 108.5 48.7 2 4.47 2 151.0 96.2 54.8 23.84 3 157.0 113.6 43.4 2 4.47 4 158.2 108.9 49.3

[0296] Knee angles indicated a yielding phase of knee flexion during thebeginning of stance followed by knee extension through toe-off. Duringswing the knee rapidly flexed and then extended prior to heel strike.Range of motion of the yielding phase and the extension phase of stanceare shown below, as is the maximum knee flexion observed during swing.TABLE 4 Knee Kinematics Knee Knee Maximum Flexion Extension knee flexionduring during during Sub- Speed Trial stance stance swing ject (m/s)Number (degrees) (degrees) (degrees) 1 4.47 1 14.7 16.1 75.5 1 4.47 214.2 12.2 81.6 1 4.47 3 19.7 27.2 78.2 2 3.84 1 13.4 27.2 76.8 2 4.47 222.1 28.7 69.4 2 3.84 3 18.2 26.1 78.0 2 4.47 4 18.5 26.7 75.0

[0297] Ankle angle ranges of motion are shown in Table 5. The ankleplantarflexed during the initial phase of stance. Ankle dorsiflexion wasobserved through mid-stance and then plantarflexion from late stancethrough the initial phase of swing. TABLE 5 Ankle Kinematics Ankle RangeTrial of Motion Subject Speed Number (degrees) 1 4.47 1 29 1 4.47 2 27 14.47 3 42 2 3.84 1 43 2 4.47 2 39 2 3.84 3 53 2 4.47 4 45

[0298] This study attempted to quantify kinematic and temporal changesin running mechanics at two speeds with two subjects across differenttypes of footwear. General observations from this study can be made.

[0299] There were few changes in the temporal measures of stride rate,stance and swing times. Subject 1 had a slightly shorter stride rate inthe third trial, meaning turnover had increased. The lack of differencesmay in part be due to the frame rate used in this study. The frame rateof 30 frames per second is inadequate to determine the precise momentsof foot strike and toe off. This study did not use a mechanical footswitch to determine heel strike more accurately.

[0300] Subject 1 had a lower vertical displacement during trial 3compared to trials 1 and 2. This could be an indication of betterrunning economy. A lower vertical displacement may indicate less energybeing expended to raise the body's center of mass, which could result inlower physiological costs.

[0301] There was an interesting difference in the kinematic parametersof the knee and ankle when comparing the trials 1 and 2 with trial 3 ofSubject 1. There was a relatively higher degree of knee flexion duringthe yield phase of stance followed by a greater degree of kneeextension. This could indicate that energy is being stored during theyield phase of trial 3 and returned to the lower extremity during thepush off phase. The energy transfer might be observed as a greater kneeextension during push off. The ankle kinematics followed a similarpattern. The range of motion of the ankle was greater in trial 3 than inthe other two trials. These differences were not noted in Subject 2across the same speeds.

[0302] It is interesting to note that the “original” energy return shoeshowed few differences from the regular running shoe of trial 1. Thepatterns described above should be examined with a more complete studyto determine if the shoe in trial 3 is significantly different than theother shoes.

[0303] 3. F-Scan Tests

[0304] Two F-Scan Tests were performed to show how Applicant's shoetends to spread out high pressure areas of the feet from the ground up.Applicant's shoe was tested against Mizuno Wave Rider Technology, whichclaims to have 22% more shock absorbency than any current midsoletechnology.

[0305] Applicant's invention had a profound ability to spread outhigh-pressure areas of the foot from the ground up. A close comparisoncan be drawn to the effect an orthotic gives to the foot. Orthoticscorrect negative foot movements from the ground up to stabilize the footin a neutral position instead of over-pronation or over-supination. Inthe forefoot, or ball of the foot, each metatarsal head gets a moreequal share of the load placed upon it. As the biomechanics place heavyloads on certain metatarsals, the load will get shared by the others.The F-scan tests particularly demonstrated the equal loading of themetatersals, significantly less amount of heel pressure when wearingApplicant's shoe.

[0306] 4. Shock Absorption Tests

[0307] Shock absorption tests were performed on Applicant's shoe and thestandard shoe. The shock absorption test uses a heel impact test machineconstructed by ARTECH, featuring a one-inch diameter steel rod guided bya pair of linear ball bearings. The rod weighs eight pounds and a threepound weight is clamped to the rod to give a total weight of elevenpounds. A five hundred pound load cell placed under the specimenmeasures force produced during impact. Force and displacement arerecorded by a computer using a 12bit data acquisition system, for 256milliseconds at millisecond intervals.

[0308] The ARTECH system uses a load cell under the specimen rather thanan accelerometer on the drop shaft. G-force is calculated by subtractingthe weight of the drop shaft and the spring force from the peak loadforce, which may offer a more direct measure of comfort.

[0309] The computer software calculates peak load and g-force asindicated above, and calculates energy return by comparing the height ofthe first rebound to the drop height at full impression.

[0310] The test data is the average of 10 drops for each style offootwear. In general, lower loads and shock (g value) suggest morecomfort to the wearer. High-energy returns, while not as critical forcomfort, may provide an appealing “spring” in the step, may reduceenergy expenditure, and may indicate a resistance to packing down of thecushion material.

[0311] To provide a general comparison to the attached test results, avery comfortable athletic shoe produced a g value of 5.4, which includedthe rubber sole, EVA midsole and sockliner. A very uncomfortableathletic shoe had a g value of 8.7 and a men's loafer 16.2 fees.

[0312] The test procedure was slightly modified while testing theseshoes. The submitted shoes were tested with the normal eleven pondweight and then with an added weight to total twenty-two pound weight.The shoes were also tested on a flat surface and at a 30° angle. Thetest results are shown in the table below. Sample ID Applicant's ShoeMizuno Shoe Property Assessed 11 lb. 22 lb. 11 lb. 22 lb. Heel Drop LoadLoad Load Load Shock Absorption Avg. (R&L shoes) “g” Value 1.12 1.091.13 1.10 Energy Returned % 83.3 86.2 82.9 79.0 Drop Height .7683 0.61110.8314 0.8107 30° angle 30° angle 11 lb. 22 lb. 11 lb. 22 lb. Heel DropLoad Load Load Load Shock Absorption — Avg. (R&L shoes) “g” Value 1.101.00 1.11 1.12 Energy Returned % 84.0 70.75 83.4 88.0 Drop Height (in.).5808 0.8438 0.5407 0.7675

[0313] 5. Physics Testing

[0314] Three general phenomenon are observed with Applicant's invention:

[0315] VERTICAL ENERGY RETURN—the shoe vertically returns or reboundsfrom where the user started.

[0316] GUIDANCE—the shoe actually moves vertically without theside-to-side movement.

[0317] CUSHIONING UPON IMPACT—the shoe continues to move for a longerduration than conventional athletic footwear, creating greater shockabsorption.

[0318] When the shoe strikes the ground while running, the userdecelerates and loses energy. Then, energy is needed to lift the footand leg up against gravity to start the next stride. Because Applicant'sinvention returns a quantifiable amount of energy to assist in liftingthe foot, heel and lower leg, less work (energy) is needed to run, andless oxygen is required to perform. This energy return can be defined asan “unweighing” of an individual.

[0319] A device was utilized that could hold any brand of athletic shoe,impacting the wall vertically and measuring recorded data from thelength of rebound off the wall, the distance each shoe returned from thewall (measurements taken at 12″ and 18″) and weighted (117 lbs) givingus the energy return data used in the testing. Shoes used: Nike AirTailwind, Nike Air Triax, Asics Gel Kayano, Asics Gel 2030, BrooksBeast, Saucony Grid Hurricane and Applicant's shoe. Applicant's shoereturned up to 22% more energy than current athletic shoe offerings.

[0320] 6. Vertical Leap Testing & Measurement

[0321] Two different methods of testing vertical leap may be performedto compare vertical leaping ability of Applicant's shoe with currentathletic footwear.

[0322] For the first test, at the University of Colorado Boulder campus,the athletic department training room uses a vertical leap-measuringdevice called a VERTECK. This device is commonly found in university,college and selected high school athletic training centers. The VERTECKis a free-standing, movable, vertically adjustable pole-like device withcolored plastic strips representing various measurements.

[0323] First, a standing vertical reach is established. Standingflat-footed, with one or both arms extended vertically and stretchingthe fingertips, the subject tries to move the plastic strips out of theway. The mark where the strips are moved—or height—represents thatsubject's vertical reach. This height also represents the starting pointfor measurement vertically.

[0324] The subject then warms up by stretching, running, bounding andjumping. Tests may be performed by a minimum of 2 subjects eachsequence.

[0325] The first subject stands directly under the VERTECK device,crouches down, then leaps vertically, knocking away the plastic strips.The measurement between standing vertical reach (or zero) and thehighest plastic strip to move is the vertical leap measurement. The testmay then proceed as follows.

[0326] Round 1:

[0327] Subject 1 uses Fila footwear—2 attempts (jumps) would bemeasured.

[0328] Subject 2 uses Applicant's shoe—2 attempts would be measured.

[0329] Round 2:

[0330] Subject 1 uses Applicant's shoe.

[0331] Subject 2 uses Fila footwear.

[0332] Continue the Rounds by the subjects until exhausted.

[0333] Record and compare all Rounds and attempts by each subject.

[0334] If the VERTECK device is not available, a second measuringprotocol may be used. As in method 1, vertical reach may be establishedby chalking the middle finger-tip of the subject and standingflat-footed, sideways to a vertical wall or 45 degree angle to avertical wall, or facing the wall. Reaching vertically, the top of thechalk mark is determined to be the vertical reach. By re-chalking thefinger-tip with each vertical leap attempt, and measuring the distancefrom the vertical reach to the top of the finger-tip chalk mark, thevertical leap is determined. For this test, Applicant recorded subjects,number of attempts and scores with each leap. An average of 10% verticalleap improvement was exhibited using Applicant's shoe versus the Filashoe in multiple attempts.

[0335] It should be appreciated that various elements from the differentembodiments described herein may be incorporated into other embodimentswithout departing from the scope of the invention. It should also beunderstood that certain variations and modifications will suggestthemselves to one of ordinary skill in the art. In particular, anydimensions given are purely exemplary and should not be construed tolimit the present invention to any particular size or shape. The scopeof the present invention is not to be limited by the illustrations orthe foregoing description thereof, but rather solely by the appendedclaims.

What is claimed is:
 1. A sole construction, comprising: a resilientlayer of stretchable material having a first side and a second side; atleast one thrustor provided on the first side of the layer, saidthrustor being made of metal; and at least one chamber provided on thesecond side of the layer adapted to receive a corresponding one of theat least one thrustor.
 2. The sole construction of claim 1, wherein thethrustor is made of a material selected from the group consisting ofmagnesium, titanium, aluminum and steel.
 3. The sole construction ofclaim 1, wherein the at least one chamber is defined by a layer made ofa metal.